Thursday, January 31, 2013

Another Beauty on Friday!

By Jay Grymes & Steve Caparotta

It was a fine Thursday and it looks like a repeat for Friday.  Just like earlier today, the young’uns will need jackets for the bus stop as we open Friday morning with a chilly start in the 30°s.  A weak cool front will slide through the WAFB viewing area on Friday, but there simply isn’t enough moisture associated with it to do more than generate a few fair-weather clouds.  Expect mostly sunny skies for the day, with the air mass on the backside of the front keeping Friday afternoon highs in the low 60°s.
So much going on this weekend ... including live music in Town Square and Mardi Gras parades ... and it looks like Mother Nature is going to cooperate for the most part.  The Krewe of Artemis kicks-off the weekend parades as the ladies take over downtown Baton Rouge on Friday evening -- comfortably cool for the 6:30pm start and looking good across the Red Stick.
A number of krewes roll on Saturday across south Louisiana – examples include Clinton (11AM), Denham Springs (2AM), and downtown BR’s Mystique de la Capitale (3AM).  Bead-catchers for those parades can expect partly cloudy skies with temps climbing into the upper 60°s by the afternoon.  The only bug for the Saturday parades is the very slight possibility of a few showers late Saturday, right in the midst of the Krewe of Orion Parade in downtown BR.  But for now, we’re giving that less than a 20% rain chance, so it looks like the Saturday night Krewe will probably be fine.  And on Sunday morning, Volunteer Fire Departments from around the area will join the Addis FD for that community’s family-oriented parade.  All in all, it will be a nice “winter” weekend topped off by the excitement of the Super Bowl late Sunday.

We stay dry for Monday, but the forecast for the Tuesday-thru-Thursday window is muddled.  For now, we’ll go with a 30% rain chance on Tuesday as a weak cool front slides into the Bayou State.  But two of our extended models (the American and the European) diverge after Tuesday in terms of rain chances.  We’ll “split the difference” between the two and keep a slight chance of rain in the forecasts for both Wednesday and Thursday.
And as we close out January, it’s worth mentioning the month’s unusual weather again!  Metro Airport’s monthly rain total of 14.67” is nearly three times the January norm and ranks as the second wettest January since 1888 -- less than 0.3” short of the January all-time record of 14.94” set in 1998.  In fact, January 2013 was the wettest month for Metro Airport since December 2009, and is tied with May 1989 as the “10th wettest of any month” back through 1888.  (By the way, BR’s “wettest” month of all?  June 2001, with 21.36” largely due to sub-Tropical Storm Allison.) Rainfall over the last 2 months also makes it the 2nd wettest December-January combined here in the Capital City.

And it was a “freeze free” January . . . which may well explain the early budding many of us have noted across the region!  On average, we get 7 to 8 freezes during January -- although a few of those tend to be rather light and very brief early morning events.  But January 2013 is the first January since 1974 with no freezes at all for the month and only the fourth “freeze free” January for Baton Rouge’s Metro Airport since 1930.

Wednesday, January 30, 2013

Mainly Clear, Cooler Rest of This Week

By Jay Grymes & Steve Caparotta

What a temperature change with the morning frontal passage: Metro Airport dropped from the low 70°s at 4:00am to the mid 50°s by 5:00am! And rain totals around the area were a bit higher than we had anticipated last evening. The advancing front earlier this morning “swelled” in size as it crossed southern Louisiana, allowing for longer-duration rains. Rather than the 0.5” or so totals we were expecting, most rains totals are running around 0.7” to 1.5” from our Weather Watchers.

Fortunately, while we’ve received numerous reports of wind gusts in the 35-50+ mph range, there was no significant damage reported, no Tornado warnings, and only one T-Storm Warning posted (for Livingston, St. Helena and Tangipahoa parishes at 5:31am). In addition, no Watches were issued for the viewing area.

Clouds stayed with us through mid-day, but skies have cleared through the afternoon. The winds will also subside as the night progresses. The combination of clear skies, light to moderate winds and a “dry” air mass now in place will allow temps to drop into the 30°s after midnight. We’re calling for Thursday sun-up temps in the mid to upper 30°s for metro Baton Rouge, with some of the northern WAFB neighborhoods - - especially north of the state line - - possible getting close to freezing for a very brief period.

Yes, our late January run of mild-to-warm weather is gone. Temps over the coming days will be something closer to normal for this time of year.

Skies stay clear through Thursday, with highs climbing into the lower 60°s for Baton Rouge. A slow warming trend for Friday, Saturday and Sunday will have metro BR weekend highs back in the mid to upper 60°s, and we’ll stay dry into early next week.

A weak disturbance late on Saturday into early Sunday may give us some overnight clouds at that time, but we don’t see any rain with that passing mid-level feature.

In the extended outlook, our next cold front arrives on Tuesday, but the signals are mixed about the strength of this boundary. For the time being, we see this as a relatively weak system, with only isolated showers possible as it moves NW- to-SE across the state.

Tuesday, January 29, 2013

Strong Storms Possible Overnight

By Jay Grymes & Steve Caparotta

We’ll be keeping both eyes on the advancing frontal system through the night.  Although widespread severe weather is not expected as the system rolls through the WAFB viewing area, we should be prepared for one or more severe weather Watches being posted between about midnight and 7AM, with isolated strong to severe storms potentially prompting some NWS Warnings. 
As with the Watches, the Warnings that are posted for WAFB communities are likely to be issued prior to sunrise.  Again, we don’t anticipate a large number of Warnings, but this system is rated by the NWS as a “Slight Risk” situation for severe weather.  The main severe threat will be straight-line winds but isolated Tornado Warnings cannot be rules out.

Fortunately, this line of storms looks to be a reasonably fast-mover, moving from west-to-east and clearing most (if not all) of the WAFB area by early to mid-morning.  By the afternoon, we expect clearing skies and cooler temps, with afternoon readings in the 60°s.

With the passage of tomorrow’s front, we’ll say goodbye to the recent run of days in the 70°s.  Temperatures will be cooler for the remainder of the work week, but they will be far from a true winter blast, even by Louisiana standards.  Thursday and Friday mornings will be chilly, with many neighborhoods waking-up in the 30°s, but only the northernmost WAFB communities can expect anything close to an early-morning freeze.  And with plenty of sunshine and afternoon temps climbing into the 60°s, there will be no complaining! 
(Actually, many of us might be happy with a good freeze or two to knock out the mosquitoes!)
This type of weather threat is a big reason why we promote NOAA Weather Radios.  Overnight storms, the ones that move over your neighborhood while you are sleeping, make the radio most valuable, alerting you to a severe weather threat before it arrives and catches you unprepared!

Monday, January 28, 2013

Windy & Warm Tuesday!

By Jay Grymes & Steve Caparotta

Tonight’s weather will include mild temps remaining in the 60°s through sunrise for metro Baton Rouge and the interstate corridor plus the potential for areas of fog for the morning commute.  Obviously the fog will be the biggest ingredient to the story, but the one inhibiting factor may be the overnight winds which will likely stay “up” just enough to keep the fog from blanketing the region.  Still, we can’t rule out the possibility of the NWS posting a Dense Fog Advisory for some parts of SE Louisiana and SW Mississippi, so be ready for the possibility for your Tuesday AM drive.

Today is the sixth consecutive day with highs in the 70°s for most WAFB communities, and it gets even warmer for Tuesday afternoon as area thermometers may approach the 80° mark!  For BR’s Metro Airport, the all-time record high for January 29th is 81° -- a few WAFB neighborhoods just might get there if they can get a little afternoon sunshine.  But for now, we think that Tuesday’s afternoon cloud cover may be just enough to keep us shy of the record.

More importantly, those same Tuesday afternoon clouds will deliver isolated showers.  We’re posting a 20% rain coverage for the afternoon, with sustained winds kicking up into the 15-20 mph range -- wind gusts through the afternoon will be even higher.

Rain chances will rapidly rise from Tuesday afternoon through the evening and into the overnight hours.  The week’s significant weather event develops late Tuesday night into early Wednesday morning as our next strong cold front pushes through the viewing area. 

Timing of the frontal passage may still need a little tweaking, but at this point we think the first pre-frontal rains will hold off until after midnight, with the front passing through metro BR between about 5:00 to 7:00am.

The early Wednesday front has some potential ingredients for active to severe weather, prompting the NWS to issue a “SLIGHT RISK” for severe weather in our viewing area.  The main threat will likely be before sun-up for metro Baton Rouge and viewers to the north and west of the Capital City, so have those NOAA radios ready.  The main threat will be damaging straight-line winds, but isolated tornadoes cannot be ruled out.

This front looks like it will be a relatively “fast-mover,” so rain totals for most neighborhoods will probably stay in the 0.25” to 0.50” range - - well below any concern for another round of flood threats, but that might be enough to add to the mess for the Wednesday AM commute in the “usual suspect” places.

But by Wednesday afternoon, clearing skies will be accompanied by highs in the 60°s.  After that, the forecast through the weekend remains dry, with temps a little closer to norms for this time of year.

Friday, January 25, 2013

Staying Warm This Weekend

By Jay Grymes & Steve Caparotta

Over the course of the past five days, we’ve been modifying the outlook for this weekend just about every day.  Earlier this week, we expected a front to slide through the state and reach the coastal waters on Saturday.  Although we never thought the weekend front would be a major rainmaker, we were carrying modest rain chances for both late Friday and early Saturday.  That was Monday into Tuesday.

Then for just about each day through the rest of the work week, we adjusted the southward reach of the front, and slowly reduced rain chances as well.  Even yesterday we were still thinking that the front would reach the I-10/12 corridor before stalling and retreating to the north: that scenario included a small drop in the daytime highs to the upper 60°s for Saturday before temps rebounded into the 70°s for Sunday.

Well, now we’re stopping the southward sag of the cool front to the north of the WAFB viewing area.  Not only does that take just about any chance of rain out of the forecast, but our update now keeps highs in the 70°s for both Saturday and Sunday.  (Frankly, we doubt that many people are really complaining about this run of dry, spring-like weather!)

So now our 7-day forecast reads “mainly dry” with highs in the 70°s through Tuesday.  For now, we’ll put a 20% chance in the forecast for the latter part of Tuesday, although the truth is we think that 20% is a little generous.

We expect our next rainmaking front to arrive Wednesday.  Two of our extended-guidance models -- the GFS (American) and ECMWF (European) -- have come into better agreement over the last day or so both in terms of timing and rain coverage.  Admittedly, given that were talking about a forecast that is still five days out, we all can expect some tweaks and twists to the mid-week forecast over the coming days.  But the outlook into next week based on our current guidance looks good.

Behind the anticipated mid-week frontal passage, we’re expecting a return to temperatures that are closer to seasonal norms, maybe even a tad below normal, at least for the short term.

So what about those parades?  all in all, looking just fine for both downtown Baton Rouge parades this weekend.  The Krewe of Jupiter & Juno kicks-off the Mardi Gras parade season for BR on Saturday evening at 6:30pm.  We may still have clouds over the city, but the temps should be pleasant throughout the evening’s parade run.  And then, starting at 10:00am on Sunday morning, North Blvd. and Town Square become “dog heaven” for the Mystic Krewe of Mutts, with the “canine carnival” running well into the afternoon under partly cloudy skies.

U.S. Drought Status Update        
 Jay Grymes / WAFB Storm Team

You’ve probably heard the rumblings regarding the persistent drought across the U.S. in recent months. According to the Weekly U.S. Drought Monitor (, well over half of the “lower 48” (57.6%) is currently rated as experiencing drought.

In truth, this reflects a very modest reduction in the drought coverage over the contiguous U.S. compared to the drought extent over recent weeks. but the drought's duration is also a big part of the national story: based on estimates by the Drought Monitor, at least 50% of the “lower 48” has been in drought since late June 2012 (7 months), with the drought extending over as much as 65% of the nation during late September.

From the nation’s agricultural perspective, the on-going drought has been a huge problem, bordering on a disaster. Drought areas include almost all of the U.S. Plains (the nation’s “breadbasket”), most of the U.S. West, and a large portion of the nation’s Southeast. In addition, the lack of rains in the Missouri and upper Mississippi basins have not only plagued farmers in the fields, but have also resulted in unusually-low flows for “Old Man River,” disrupting transportation and delivery of a large proportion of the U.S.’s agricultural products.

While sections of the Bayou State have fallen under drought over this seven-month period, Louisiana as a whole -- including most of the WAFB viewing area -- have fared reasonably well. We did have a rather dry stretch during the fall, but for most WAFB communities the dry spell flip-flopped dramatically during December and early January. Indeed, many within the WAFB viewing area have endured near-record rainfall for this time of year over the past eight weeks. A number of sites in the region are reporting 20” to 25” of rain or more since December 1 -- more than three times the norm!

Yet a look at rainfall across the entire state shows that a number of southeastern parishes have missed out on the excessive winter rains. In fact, rains are running below normal since December 1 from sections of metro New Orleans to Galliano to Grand Isle to Boothville, with some locations in southeastern Louisiana reporting 70% or less of the normal rainfall for the recent eight week span.

This is a great example for us: even for a relatively small state like Louisiana, short-term weather and climatic differences can be quite large, and just because "it’s happening in your backyard” doesn’t mean that everyone in the Bayou State is experiencing the same circumstances!

Thursday, January 24, 2013

Spring-like Weather Continues Friday

By Jay Grymes & Steve Caparotta

Are you enjoying our run of spring-like weather?  Well, even if you would prefer a little January chill to the air, you’ve got to admit that this is far better than the wet streak that dominated the first half of the month.
A cold front is still on track to arrive over the WAFB viewing area late Friday into early Saturday, but as we discussed yesterday, it is expected to stall and weaken across the southern parishes on Saturday.  Whatever is left of the frontal boundary is then expected to lift northward as a warm front on Sunday. 

So given the slow-moving nature of the weekend front, why so dry?  Largely because the surface boundary will have little mid- and upper-level support: a lack of “deep” moisture in addition to little help from the upper levels to generate sufficient lift to produce rain.  Yes, we’ll have a good dose of cloud cover, and we may see a couple of sprinkles pop-up on Doppler radar early Saturday morning, but it won’t amount to much if anything.
Our forecast now keeps Baton Rouge metro lows in the 50°s through the weekend, with highs on Saturday in the upper 60°s.  Afternoon temps will return to the 70°s for Sunday.
The Krewe of Jupiter and Juno, celebrating their 10th anniversary, will once again serve as the first parade of the Mardi Gras season for Baton Rouge -- that’s downtown this Saturday evening.  Temps should be comfortably cool for the parade, running in the low to mid 60°s for the parade’s 6:30pm kick-off and easing down into the 50°s by parade’s end.

Mystic Krewe of Mutts takes over downtown BR on Sunday morning, with registration starting at 10:00am, and the “canine carnival” continuing well into the afternoon.

We’re calling for more highs in the 70°s for Monday, Tuesday and Wednesday.  Monday will stay dry under a sun/cloud mix, with a modest rain chance developing for WAFB communities on Tuesday. 
Our key extended-outlook models are sending mixed signals regarding the mid-week front expected to move through the lower Mississippi Valley, differing both on timing and rain potential.  For the time being, we’re staying with a good chance of rain (50% - 60%) on Wednesday, although confidence is somewhat low.  Admittedly, that’s well down the “forecast road,” and we’ll have to keep an eye on the various guidance packages to see if they start to show signs of better agreement in the coming days.
And for those that like a little trivia: as we mentioned a few days ago, it’s been a relatively mild month temperature-wise with no freezes, and our extended forecast says the “freeze-free” pattern will continue through month’s end.  That is rare for January, having only occurred during three prior Januarys (based on records back to 1930).  But don’t be fooled into thinking that it has been a “warm” month.  Believe it or not, January 2013’s monthly average temperature through today  -- that is the average of each daily high and low -- is 52°.  That’s right at “normal” for the 24-day period.

Wednesday, January 23, 2013

Fog Possible Next Couple of Mornings

By Jay Grymes & Steve Caparotta

Areas of morning fog will be our primary weather concern over the next couple of days. Warm, moist air moving inland from the Gulf of Mexico over somewhat cooler land areas will result in areas of what we call sea (or advection) fog. The National Weather Service in Lake Charles has already posted a Dense Fog Advisory for parts of south-central and SW Louisiana.

So it’s back to the 70°s for the next couple of days, but Mother Nature has thrown us a curve ball over the last 12-24 hours, changing up the forecast for Friday and through the weekend.
We still expect a front to ease its way over south Louisiana by the latter half of the day Friday and into early Saturday morning.  What has changed is that now it’s looking like it will be a “mainly dry” boundary, producing little, if any, measurable rainfall over the WAFB viewing area.  The front looks like it will essentially stall along or near the Louisiana coast, then either fizzle out or drift northward as a weak warm front Saturday into Sunday.
The main point is that we stay mainly dry and the temperature drop we anticipated for the weekend will be much smaller than what we’ve been forecasting for the last couple of days.  If you remember, while our prior weekend forecast was dry, we were calling for highs in the 50°s on Saturday and around 60° or so for Sunday.  Now, we’re thinking that we’ll keep a very slight chance of rain in the Saturday morning forecast, with partly cloudy skies for Saturday afternoon and Sunday.  In addition, look for highs in the 60°s for Saturday and up near 70° for Sunday -- great news for area parades!
Yes, it’s kick-off time for BR’s Mardi Gras Parades!  The ‘Red Stick’ parade season starts with the Krewe of Jupiter & Juno on Saturday evening (6:30-9:00pm) along its downtown route.  Then on Sunday at 10:30am, North Boulevard goes to the dogs, with the Mystic Krewe of Mutts festivities.

Heading into next week, it’s more daytime highs in the 70°s for Monday, Tuesday and Wednesday.  With a southerly flow in place, we’ll put very low rain chances in the forecast for Monday (10-20%) and Tuesday (20-30%).  The extended guidance timing still needs some tweaking, but for now we anticipate a more potent cold front to arrive Wednesday, with rain likely then.

Tuesday, January 22, 2013

Warming Up Next Few Days!

By Jay Grymes & Steve Caparotta

Although it was cooler today than during the previous few days -- as we expected -- today still proved to be another January beauty.  We continue a much-deserved run of nice weather and we continue to dry out after the “mega-wet” start to the month.  In fact, today’s high and low temps were just about “normal” for this time of year.
Metro Baton Rouge can expect another cool night and early start for Wednesday, with temps dipping into the low to mid 40°s under clear skies.  Wednesday afternoon, however, will be noticeably warmer, with highs reaching 70° or more for many WAFB neighborhoods under mostly sunny skies.
Our forecast keeps highs for the ‘Red Stick’ in the 70°s for Thursday and Friday too.  After a mostly sunny Wednesday, plan on partly cloudy skies on Thursday, with our next cold front approaching from the west on Friday. 
Computer model guidance is still giving mixed signals as to what Friday’s front will do in terms of rainfall as it passes through our area.  We’re sticking with our thinking from yesterday, calling for only limited rain coverage (about 30% or so) and little in the way of rain totals (under 1/4” for just about everyone, many getting less than 1/10”).  We’ll watch closely over the next 24-48 hours to see whether the models come into better agreement.
What we do expect on the backside of Friday’s front is another dose of very cool -- but not really cold -- weather.  Highs for the weekend will be in the upper 50°s to around 60°, but the weekend should be good for some “outdoor” time.  Plan on mainly sunny skies for Saturday and fair to partly cloudy skies on Sunday.
But the weekend’s cool spell doesn’t hang around, as our extended forecast calls for a return of highs at or above 70° early next week.

Speaking of temperatures, it has been a rather mild winter thus far across the WAFB viewing area, with temperatures since December 1 averaging 2° to 3° above normal for most of the viewing area.  Admittedly, 2° to 3° isn’t that big of a deal, but what is especially noteworthy is the low number of freezes thus far this winter. 
Using Metro Airport (BTR) as an indicator, we find that BTR averages about 13 freeze days from through January 22nd (today).  So far this winter, however, BTR has recorded just 5 freezes, and none so far during January -- on average, BTR has 8 freeze days during January alone!  BTR’s 5 freezes thus far this season ties for the 5th lowest number of occurrences (through Jan 22) since 1930.  And for McComb, the 8 freezes at that location this season through today is tied for the fewest ever!

Okay, let’s hope we just didn’t jinx things!
And for you trivia-minded, Baton Rouge’s daily normal temps tell us that, climatologically, January is the area’s coldest month -- no surprise there, right?  BTR’s daily normals (high: 62°, low: 41°) have been unchanged for the past three weeks.  Well, those normals will start to “inch upward” ever so slowly by week’s end, our first indicator that spring is not too far down the road!  Well, okay, it’s not just around the corner either . . . don’t be putting away the heavy blankets just yet!

Monday, January 21, 2013

Mostly Sunny, Cooler on Tuesday

By Jay Grymes & Steve Caparotta

Yep ... a pretty nice day for MLK Jr. and Inaugural celebrations!  And most of the week looks pretty good too!

You probably won’t notice it this evening, but we’ve got a cool front sagging southward through the state.  By later tonight that front will be over the Gulf waters and continuing a southward push.  Behind the front, we’ll get a moderate drop in our local temperatures, but not a return of a winter-like chill.

Titan9 PrecisionCast depiction of conditions at 1 AM Tuesday showing a cool front moving offshore.
A core of surface high pressure over the Northern Plains will move towards the southeast rather than south, so that the real chill remains to our north and northeast.  But we will see many WAFB neighborhoods dipping into the 30°s for Tuesday’s wake-up.  And while skies will be mostly sunny for Tuesday afternoon, highs will only inch their way into the low 60°s for metro BR.

After another cool start near 40° for the ‘Red Stick’ on Wednesday morning, temps will show a slow-but steady warm-up into Friday.  At the same time, we’re expecting our next frontal passage during the latter half of Friday.  The guidance remains a little on the Friday solution in terms of the rain potential, but for now we’re going with scattered showers (rain chances only about 30% or so) and rain totals generally under one-tenth of an inch.  No need for concerns among those living along area rivers and bayous.

Friday’s front will deliver another shot of cool -- but not cold -- air, as once again, the surge of coldest air behind Friday’s front will stay to our north and northeast.  Look for morning lows over the weekend in the 30°s and 40°s, with highs in the 50°s.  All in all, the weekend looks pretty good, with sunshine expected for both Saturday and Sunday.

For the time being, we’re calling for only slight rain chances next Monday.

Friday, January 18, 2013

Nearly Perfect This Weekend!

By Jay Grymes & Steve Caparotta

Friday makes a second straight day with sunshine and blue skies, and the weekend will keep pace with mainly sunny skies expected for both Saturday and Sunday.  Plus, the weekend gets a little warmer, with highs both days in the mid to upper 60°s!

A broad surface high pressure ridge extends from the mid-Atlantic to the Lower Mississippi Valley, making for a nice winter day throughout the U.S. Southeast.  That ridge will remain the primary controller for our weather through Saturday.  Believe it or not, we do anticipate a front sliding from north-to-south through the region on Sunday, but it will be a “dry” front. So dry, in fact, that not only will it be rain-free, but we don’t even expect much in the way of clouds as it moves through. 

On the back-side of the front, we’ll get another dose of dry and cool Canadian air.  Yet even then, we’re not talking about a major drop in temperatures for Tuesday into Wednesday.  And again, staying dry through mid-week.

By Thursday, winds will swing back around allowing for a warmer day, but still rain-free.  As it looks right now, our next rain-maker won’t arrive until Friday at the earliest.  Model guidance suggests that the core of our next significant weather disturbance will pass well to the north of Louisiana late next week, but the trailing front associated with that system will move west-to-east through the Bayou State.  That’s too far down the road at this stage to offer any real confidence regarding rain chances, potential amounts, or any ‘severe’ threat.  We’ll watch it for you through the weekend and into early next week.

 In the meantime, have a great weekend and try to enjoy some of the sunshine!

Thursday, January 17, 2013

Mainly Sunny, Dry Days Ahead!

By Jay Grymes & Steve Caparotta

Boy, oh boy ... the sun never looked so good!
Skies should stay mostly clear overnight and into the morning.  It gets cold again though, with lows dropping into the low 30°s for metro BR.  That means a light freeze for many communities along and north of the I-10/12 corridor, but not a big deal in terms of temperatures or freeze durations.
The forecast stays mainly sunny for Friday and right through the weekend – that’s got to be much welcomed news for just about everyone!  And we’ll warm it up a bit too, with highs in the upper 50°s for Friday and into the 60°s for the weekend.
Obviously the dry weather is good news for folks along our area rivers and bayous, but we all could benefit from a good run of dry weather given the region’s waterlogged backyards, fields and pastures.  And Mother Nature cooperates: not only do we stay rain-free through the coming weekend, but the extended outlook keeps us mainly dry right through next week and into next weekend, at least!
We will have another front pass through the state on Sunday, but it will be a dry Canadian front.  We’ll feel a little dip in temps on the backside of the front with the cooler air-mass in place, but the frontal passage will do little more than generate a few clouds for south Louisiana.

Now, for you trivia buffs, let’s take another look at the rainfall thus far for January.  Metro Airport is reporting 13.81”, with January-to-date reports from across the WAFB region ranging from 10” to 18”!  And to our west, in Eunice, they’re reporting a whopping 20.29” already this month - - the equivalent of 4 month’s worth of normal rainfall!
For Baton Rouge (Metro AP), the 13.81” is the largest monthly total since December 2009 (14.86”), and already ranks as the second “wettest” January on record (data back to 1888), topped only by 14.94” during January 1998.  Although our forecast keeps us dry through the next seven days, that January 1998 all-time record might still be in jeopardy.

A look at all months back to 1888 -- that’s 125 years, or 1500 months – ranks our January 2013 rains already at #18 for all-time high monthly totals, in the top 2% of all months!  When we look at it in those terms, it’s somewhat surprising that the flood damage hasn’t been worse.
And by the way, what was the “wettest” month ever for Baton Rouge based on these records?  You probably remember June 2001’s Tropical Storm Allison, which helped take that month’s total to 21.36”.  The only other over-20” month in the time series was back on November 1929.

Wednesday, January 16, 2013

Snow Tonight/Thursday AM?

I woke up to this morning to a few questions on social media asking about snow being mentioned in the forecast by some outlets. I was a bit surprised since we had downplayed the threat Tuesday night, but an examination of the latest computer guidance in this morning shows why that magical 'snow' word is being tossed around.

The prospects for any wintry weather are tied to a fairly potent upper-level low forecast to move across the area late tonight into Thursday morning.

NAM (computer model) forecast valid at 3 AM on Thursday. An upper-level low is noted moving across central/northern Louisiana.
The upper-level low is important for 2 reasons: 1) it generates 'lift' that can lead to the development of clouds/precipitation, and 2) these upper-lows carry pockets of cold air aloft in the atmosphere necessary for frozen precipitation.

Most guidance shows that the atmospheric profile (temperatures from near the surface to several thousand feet above ground) will be plenty cold enough late tonight to support wintry precipitation, primarily in the form of snowfall. The big question remaining is: will there be enough moisture left?

Yesterday, our computer guidance was unanimous and adamant that necessary moisture would exit the region well before the arrival of the upper-low. The big change with this morning's guidance is that much of it now hints at just enough moisture lingering to squeeze out some very light precipitation late tonight.

Our RPM model now generates some light snow near the state line into SW Mississippi near/after midnight tonight...

RPM forecast valid at 2 AM Thursday. Snow is represented by shades of blue and white. A wintry mix is represented by the pink shading.
RPM forecast of snowfall potential through Noon on Thursday. 
Here's the key...while the odds of a little wintry precip/snow may have increased a bit this morning, we still believe anything that falls should be quite light. The greatest chances for any wintry precipitation appear to be near the LA/MS state line northward into SW Mississippi. Even here, significant accumulations appear unlikely, although it's possible a little snow could briefly accumulate on trees/grass and elevated surfaces.

Here's another look at snow potential...the graph below shows that the NAM (computer model) is forecasting about 1/3 inch of snow at McComb, while the GFS only generates about 1/10 inch.

The same plot for Baton Rouge shows the models have no snow accumulating in the Capital City, although I wouldn't completely rule out some flurries or very light snow late tonight.

Bottom line: even if anything falls tonight...and it's still a big 'IF'...significant accumulations are not expected. Of course, Jay and I will have the latest on 9News at 5 & 6 this evening.

Tuesday, January 15, 2013

Rains Finally Diminishing Wednesday

By Jay Grymes & Steve Caparotta

Some WAFB neighborhoods saw as much as 0.5” to 1.0” of rain today, adding to the region’s record-approaching January totals, but thankfully these amounts were not so much as to prompt new rises on most area rivers.  We continue to watch water levels show very slow falls along most area waterways, although the lower reaches of the Amite have remained essentially “flat” through most of the day.
The weather story now shifts from rain to cold.  Today was yet another rather disagreeable day weather-wise, with highs for some of the northern WAFB communities barely making it into the 40°s!  Add in the damp air and the northerly breezes and it certainly felt much colder.
We’ll keep on-and-off passing, mainly-light, showers in the forecast through tonight and Wednesday morning, with the rains coming to an end for most of us by or before mid-day Wednesday.  Some could even see some peaks of sunshine late Wednesday afternoon, with skies clearing across the region from Wednesday evening into early Thursday.

Along with that clearing will come the main shot of a Canadian air mass, with temps dipping below freezing for many WAFB communities by Thursday morning.  You may have heard about some potential for “winter precipitation” this week, especially for northern portions of the WAFB viewing area.  The air will certainly be cold enough by late Wednesday night into early Thursday, but we think that the moisture will get out of the area well before the freezing temps arrive, eliminating any serious potential for snow, sleet or freezing rain.
Plan on sunshine for Thursday, Friday and Saturday. 
After a freezing wake-up, temps will climb into the mid 50°s under the sunshine for Thursday. Much of metro Baton Rouge will drop back into the low 30°s for Friday morning, with light freezes possible for neighborhoods near and north of the I-10/12 corridor, but afternoon readings should return to the mid to upper 50°s for Friday afternoon.

The weekend is looking good, with highs back into the 60°s and a continued and much-welcomed dry-out.  And the forecasts show that most, if not all, area rivers should be back below flood stage over the weekend.

Tuesday, January 8, 2013

Flash Flood Watch Into Thursday

By Jay Grymes & Steve Caparotta

As of 5PM, much of the Baton Rouge metro area had already received upwards of one-half-inch of rain, with generally light-but-steady rains continuing to fall over the ‘Red Stick.’  The rain through the overnight is expected to remain fairly constant as well, and falling at slightly higher rates than we’ve seen this afternoon.
A FLASH FLOOD WATCH has been in effect for areas west of the Atchafalaya Basin, and a new FLASH FLOOD WATCH -- which includes most of the WAFB viewing area - - was issued this afternoon and remains in effect until 6PM Thursday.

We’re still awaiting the passage of the anticipated warm front that we described yesterday.  That likely occurs tomorrow morning, which means rain likely not only through the night but through the morning hours too.  Looks like a very wet morning commute.  Lows tonight likely remain in the 60°s for many of us, with highs on Wednesday climbing into the 70°s as we move into the “warm sector” (the south side of the warm front).
While we think there will be breaks in the rain during Wednesday afternoon, we still expect showers and possibly a few t-storms through the day.  As we head into Wednesday night and early Thursday, our attention will turn to the west with the approach of a cold front.
As we noted yesterday, the advancing cold front does not look like it will be an especially fast-moving boundary, so the timing through Thursday is still a bit in question.  For now, we’ll call for scattered showers and t-storms Wednesday night, with “showers and t-storms likely” for Thursday morning.  For the time being, it looks like rains will slowly end from west-to-east during the afternoon and evening.
The NWS Storm Prediction Center still has most of the viewing area under a “SLIGHT RISK” for severe weather for Wednesday into Thursday morning. The primary threat will come as a cool front approaches from the west on Thursday.
Models continue to show differences, but it appears as though 2” to 4” for much of the WAFB viewing area between now and Thursday is very reasonable, with locally higher totals.  Not only is this range sufficient to warrant a WATCH, but we’ll need to monitor rainfall trends closely: 4” of rain could become problematic for area rivers.
Projected rainfall totals through Thursday afternoon from the RPM model (left) and GFS model (right). The RPM seems to be running a bit high, but isolated rain totals of 6" to 8" are possible.
It looks like we’ll get a short reprieve from the rains on Friday, but we’ve got our next frontal system moving into the area late Saturday into Sunday, with the system potentially stalling along the coast, keeping rains in the forecast through the early part of next week.

Monday, January 7, 2013

Wet Weather Returning...

By Jay Grymes & Steve Caparotta

Given our rather cool, cloudy and damp start to 2013, today’s sunshine was a welcomed sight!  But you’ve probably already noticed that today’s blue skies were short-lived: the clouds are moving in from the west and will continue to “thicken” into the night.

Yep -- keep the umbrella within reach, just about all week long!

We’ll start off Tuesday under the clouds but dry ... and not quite as cool as Monday’s start for the kids at the morning bus-stop with sunrise temps on Tuesday in the mid 40°s around metro Baton Rouge.  Tuesday afternoon will be a bit warmer as well, with highs expected to reach the upper 60°s for many WAFB neighborhoods.  But during the afternoon, especially the latter half of the afternoon, we expect rains to start moving in from the southwest and west.  It looks like scattered showers and maybe a few rumbles of thunder for the Tuesday evening commute.

By Tuesday night into the early hours Wednesday, just about everyone gets wet again.  But the warm-up continues as a warm front lifts northward from the Gulf. 

An upper-level storm system over northern Mexico will help strengthen a developing surface low pressure system over south Texas.  The warm front that slides through the viewing area from late Tuesday into early Wednesday will be tied to that Texas low ... as will a trailing cold front.

But this Texas storm complex will be a bit of a slow-mover, with the low still to our west late Wednesday into the early hours Thursday.  We will be in the “warm sector” ahead of the system, and that should help take highs on Wednesday into the 70°s.  We’re thinking that the rains will taper off a bit by Wednesday afternoon and into the evening hours, with much of the area remaining mainly dry into early Thursday.

By Thursday morning, with the surface low to our northwest and moving north, the forecast calls for the system’s cold front to begin its advance to the east.  This set-up over the next couple of days offers the potential for some energetic storms, prompting the NWS Storm Prediction Center to post a “Slight Risk” for severe weather across most of the WAFB viewing area from mid to late Wednesday into early Thursday.  (We’ll have to see if that threat is extended into the middle of the day on Thursday.)

With this slow-moving system and a very “juicy” atmosphere, the bigger threat may well be the potential for a serious rain event over the coming days.  While it looks like the heaviest regional rains will stay to the west of the Atchafalaya Basin, we can’t rule out some 2” to 3” rains across our viewing area, with localized totals possibly going even higher.  Thankfully, most of the area rivers and bayous are in decent shape for handling a big rain event as long as areal averages don’t get too large!

 Most of us will get another brief break from the rains on Friday, but our current weekend outlook has rain returning, especially for Sunday!

Friday, January 4, 2013

Gloomy Weather Returns Saturday

Friday got off a rather chilly start, but just about all of our official reporting stations stayed just above freezing. Metro Airport saw a low temperature of 33° just after sunrise. And even with a decent amount of sunshine at times this afternoon, highs only reached the mid 50°s for most of us.

 Gloomy weather returns as we move into the first weekend of 2013. Skies will likely become overcast during the overnight and we can’t rule out a few sprinkles. We then look for cloudy skies, cool temps and scattered showers during the day on Saturday. Rains shouldn’t be that widespread and will for the most part be rather light, but any showers will just add to the unpleasant feel on Saturday. The clouds and showers will again keep highs in the mid 50°s for most.

 A few showers could linger into Sunday morning, but we expect some improvement by the afternoon – including the possibility of some sunshine before the day is up. We’ll then enjoy a rather nice winter day on Monday before things yet again start to go downhill.

An approaching storm system will bring a return of clouds and the chance of a few showers by Tuesday. After that, there are big question marks both on the timing of our most significant rains and the degree of cool-down we see, if any at all.

Right now, we’re leaning towards the heaviest rains arriving on Wednesday and possibly lingering into a portion of Thursday. There is also some indication of a possible severe weather threat, but we’ll get a better assessment of that as the event gets closer. The same model that points toward a slower arrival of rains also keeps temps mild during the latter half of the week, so that’s what we’ll go with for now.

Have a great weekend!

Wednesday, January 2, 2013

Hoping for a Little Sun on Thursday!

Do you have a case of the ‘winter blues’? Yet another dreary and chilly day may have left you feeling a bit sluggish, with temps stuck in the 40°s, along with off-and-on drizzle and light rain. There have even been isolated reports of very light sleet today, and we can’t rule that out for this evening, but anything falling in a frozen form would be VERY light and there are no concerns with accumulation.

Clouds and occasional bouts of light rain/drizzle will continue into the overnight hours as Pacific moisture continues to stream up-and-over a shallow mass of cold air at the surface (something meteorologists refer to as ‘overrunning’). However, strengthening high pressure to our north is expected to shunt most of the moisture offshore by daybreak on Thursday.

The big question then becomes, will we see any sunshine? It appears to be a close call, with better chances of some sun north of the interstates and higher likelihood of remaining overcast closer to the coast. We’ll call it mostly cloudy for Thursday, although some areas to the north will likely see more in the way of sunshine.

Even if the sun does make an appearance in your neighborhood on Thursday, it looks as though clouds will quickly return by Friday as our next storm system approaches from the west. We’ll keep the Friday forecast dry, but scattered showers return to the area over the weekend. Right now, I’ve got rain chances posted at 30% for Saturday, but it’s possible I may have to look at increasing those a bit over the next couple of days.

Cool weather stays with us through the weekend, with a modest warm-up expected into next week.