Tuesday, April 30, 2013

More Rain on the Way

By Jay Grymes & Steve Caparotta

Our WAFB Storm Team forecast has become progressively “wetter” over the past 24 hours thanks to an upper-level low just to our west and an almost summer-like air mass in place over the Gulf Coast region.

On Monday evening, we showed you the developing upper low as it spun over Texas and produced widespread showers and t-storms along the Texas Gulf Coast.  That feature has now moved east and is located near the TX/LA state line and is serving as the prime trigger for this afternoon’s rains.  If you’ve seen the afternoon radar presentation, as of 3:30PM we had a rainband-like feature stretching from the northern Gulf into southeast Louisiana and right through the BR metro area.  The elongated rainband, which included numerous t-storms with a few on the strong side, was rotating counterclockwise around the upper low to the west..

Unfortunately, the upper low is not expected to move much over the next day or so, lingering over the region into Thursday -- that means more rain ahead.  Add to that our continued forecast for our next cool front to slide into the WAFB viewing area during the latter half of the day on Thursday, which will serve as an additional focus and lifting mechanism for the moist, Gulf air mass.

It looks like Thursday’s front may be a little slower in clearing the region than we had thought on Monday, so we’ll increase rain chances for Friday, especially during the first half of the day.  With a little luck, we’ll get the showers and most of the clouds out of the viewing area by Friday evening.

So is there any good news?  Well, a little -- while we expect the rains to linger into Friday, we don’t anticipate a severe weather outbreak in this set-up.  On the other hand, the not-so-good news is that we are likely to see some significant rains over the coming days.  The latest NWS Weather Prediction Center (WPC) rain outlook calls for widespread 1” to 3”+ rain totals for the WAFB viewing area with locally higher totals. In fact, the National Weather Service has posted a Flash Flood Watch for parishes south of metro Baton Rouge and around metro New Orleans.

Don’t be shocked to see some multi-day reports of as much as 4” -- and even one or two 5” totals somewhere in southeast Louisiana -- between now and Friday afternoon.   Given that rain potential, we may be watching the local rivers very closely by the end of the work week.

So stay dry and be sure to grab the umbrella on your way out the front door tomorrow morning!

By the way, tomorrow -- May 1st -- marks the official start of the “Louisiana Ozone Season.”

Monday, April 29, 2013

Unsettled Weather Much of This Week

By Jay Grymes & Steve Caparotta

Our forecast for Tuesday and Wednesday calls for highs in the 80°s and morning minimums in the low 60°s.  But the bigger part of the weather story for the next few days is the increasing rain chances: we’re calling for scattered afternoon showers and storms for Tuesday and Wednesday with an even better chance of rain on Thursday as the Gulf Coast region’s next cool front slides by.

Titan9 Doppler picked up a few showers today, mainly over the coastal parishes.  A relatively warm and moist low-level Gulf air mass is in place and will remain with us into Thursday as the flow persists off the Gulf.  Daytime heating (and sunshine) will help the moderately unstable atmosphere kick-off scattered rains for the next two afternoons.  In fact, our in-house RPM model has the look of a summer-like sea-breeze pattern setting-up for Tuesday afternoon.

In addition, the moist Gulf air will likely cool sufficiently during the pre-dawn hours for the onset of fog over the next couple of mornings.   We’ll have to keep a close watch on early-morning air-temperature/dewpoint pairings.  The air becomes “saturated” (100% relative humidity) when the air temp and the dewpoint become the same, and saturation encourages fog formation especially when the winds are light or calm.   Another prolonged run at saturation during the early morning hours on either Tuesday or Wednesday could prompt the NWS to issue a Dense Fog Advisory like we saw earlier today.  However, at this is not a major concern at this time, just something to be aware of.

A series of lows well to our north and northwest will continue to track from west-to-east in the coming days.  By Wednesday, however, a storm system currently over the U.S. Northwest will push a cool front into the Southern Plains.  The core of this mid-week storm system -- and the main concerns for severe weather -- will remain to our north, based on what we see right now.  But the trailing cool front expected over the Southern Plains on Wednesday will track eastward from Thursday into the weekend. 

The NWS Weather Prediction Center (WPC) has that front extending from the Great Lakes to the Texas Coast on Thursday morning and positioned just east of the southeastern coastal parishes by Friday morning.  This set-up brings the boundary through the WAFB viewing area during the latter half of Thursday.  We’re expecting a decent rain chance with Thursday’s front, in the form of showers and t-storms -- for the time being, we’ll go with a preliminary forecast for a 60% rain chance from the latter half of Thursday into the early hours on Friday.

In the extended outlook, we expect clearing skies during the day on Friday with a much cooler air mass in place.  We’ll see how it shapes up in the coming days, but some of our early guidance is hinting at highs not even making the 70°s for many WAFB neighborhoods on Friday afternoon!  And the weekend is looking pretty good right now – a fine Saturday and a mainly-dry Sunday with highs in the 70°s for both days.

Friday, April 26, 2013

Good Rain Chances by Sunday

By Jay Grymes & Steve Caparotta

Friday afternoon turned out to be an active mix of sunshine and clouds: nearly-clear skies over many WAFB communities around the lunch hour but skies becoming mostly cloudy for most WAFB neighborhoods by the mid-afternoon.  You also may have noticed the air becoming more humid as the day progressed thanks to persistent low-level southerly flow.  Dewpoint readings rose from the upper 40°s near sunrise into the 60°s by the afternoon thanks to the inflow of Gulf moisture -- not oppressive by any stretch, but enough to ‘feel’ the difference.
The moist air mass stays with us through the weekend, keeping morning lows in the 60°s for both days and helping fuel wet weather for Sunday.  Fortunately, Saturday is looking “mostly dry” -- were going with rain chances at less than 20% (“isolated”) for Saturday afternoon with highs in the low 80°s under partly-sunny/mostly-cloudy skies. So, while Live After Five, LSU baseball, Jazz Fest and many other outdoor events will be fine tonight, the news isn't so good for the latter half of the weekend.

A mid/upper-level disturbance currently to our north will slowly move eastward while a cold front associated with this system becomes better-defined, extending from Arkansas into Texas on Saturday.  By Sunday, that front will begin a steady march to the south and southeast through Louisiana, delivering showers and t-storms along the way.  At this point we are not too terribly concerned about a widespread severe weather outbreak on Sunday (like we suffered Wednesday morning!), but be prepared for a few t-storms to become strong to severe.  IN addition, the NWS has noted a concern for locally-heavy rains on Sunday afternoon and evening, in part due to the expected slow movement of the boundary.

In addition, the guidance has the front slowing and possibly stalling near the coastal zone -- that helps keep decent rain chances in the forecast for both Monday and Tuesday.
In the extended outlook, we’re anticipating south Louisiana’s next frontal system moving from the U.S. Northwest into the U.S. Plains between Tuesday into early Wednesday.  That mid-week front will continue towards the central Gulf Coast region late Wednesday into early Thursday.  That should mean another round of rains and t-storms, but the guidance is also suggesting that system moves through fairly quickly, with a dose of cooler and much drier continental air settling into the viewing area on Friday.

Thursday, April 25, 2013

Warmer, Spotty Showers on Friday

By Jay Grymes & Steve Caparotta

Showers skirting the southwestern and south-central coastal parishes this afternoon are expected to remain there, and while we did see a few returns on Titan9 Doppler this afternoon, the fair skies for most neighborhoods were greatly appreciated. 
It looks like we’ll start out Friday with another round of partly-to-mostly cloudy skies and lows in the low to mid 50°s.  Plan on a sun/cloud mix for Friday afternoon, with highs in the low 80°s and increasing low-level moisture thanks to southeasterly winds.  We may see a few blips on Titan9 Doppler radar during Friday afternoon, but most stay dry through the day -- so we’ll give it a weather grade of “B” for downtown’s Live After Five.

The forecast for Saturday is looking a bit better than it did just a day ago.  We’re keeping a slight chance of rain in the Saturday afternoon forecast but dropping it to about 20% or so, compared to previous forecasts that were calling for rain chances of around 30% for Saturday afternoon and early evening.  We still expect a disturbance and an associated frontal system to develop to our north on Friday into Saturday, but it looks like the main energy remains to our north through Saturday evening.

While the Saturday outlook has improved a bit, not so for Sunday.  The system that will be to our north on Saturday will sag southward on Sunday, enhancing the likelihood of afternoon showers and t-storms.  We’re thinking a 50-50 chance of rain for your back yard for Sunday afternoon and evening.

Unfortunately, we don’t expect a significant cool-down following Sunday’s rains, nor are we anticipating a nice run of dry weather.  We’re keeping forecasted highs up around the 80° to 83° range for Monday and Tuesday, with rain chances both days in the 30% to 40% range.

The current extended guidance has our next front arriving in the Bayou State very late Wednesday or early Thursday, keeping our mid-week outlook very unsettled.  We should see some improvement by next Friday.

Wednesday, April 24, 2013

A Rough Start to Wednesday!
-- 24 April 2013

A rough and tumble start to the morning with a Tornado Watch and a series of Tornado and Severe T-Storm Warnings across the WAFB viewing area. Add to that rains of 1” to more than 2” for some communities! Quite the mess for the morning, especially when we consider that the forecast tools yesterday certainly didn’t give any indication of a severe-weather outbreak to start the day!
We had a couple of reports of wind-related damage in the viewing area during the morning, but as of 3PM there have been no confirmed tornadoes in any of our WAFB communities. Flooded streets, however, was a very different matter. Fortunately, the heaviest rains lasted for less than one hour for most neighborhoods and as of this afternoon many roads that had standing water earlier in the day are well-drained and ready for the evening drive.
In addition, it looks like the front that delivered this stormy weather will push out into the Gulf far enough to leave us with a mainly-dry forecast for Thursday and Friday. If you remember, yesterday we were concerned that the front would stall near the coast, keeping rain chances in the 20% to 30% range for the next two days. While the latest guidance still suggests that the front sill stall in the northern Gulf, it will be offshore far enough to provide a couple of days for a much-appreciated dry-out.
Unfortunately, the weekend outlook is not as rosy. We’ve got a 30% rain chance posted for Saturday and scattered showers and t-storms in the Sunday forecast. Our forecast remains unsettled through the first half of next week too, with rain chances at about 30% for Monday and Tuesday and another cold front scheduled to arrive around mid-week.

Tuesday, April 23, 2013

Showers, A Few T-Storms on Wednesday

By Jay Grymes & Steve Caparotta

As our Thibodaux Weather Watcher, Barbara Koscher, said in her daily report: “You can feel it.” She was referring to the increased humidity, which kept Tuesday morning lows in the 60°s across the area and will do so again tonight and into Wednesday morning.

Expect clouds and patches of fog for Wednesday morning, with a spotty shower or two possible, especially closer to the coast. Rain chances will increase through the day: we’re posting probabilities at 60% to 70% for Wednesday afternoon and evening thanks to an advancing cold front. The clouds and rain should keep Wednesday’s highs in the 70°s.

A look at Titan9 Doppler shows little if any rain anywhere near the front -- currently draped from Arkansas into East Texas -- but we expect the boundary to “moisten up” as it draws enters the Bayou State and moves towards the viewing area. 

We’re getting some mixed signals from some of our forecast tools, but we’re thinking rains on the order of about 0.25” to 0.75” for this event. The good news is that while we can expect a few t-storms with this front, there appears to be little in the way of a “severe weather” threat with this go-around.

Unfortunately, the front will slow and likely stall as it moves into the coastal zone and northern Gulf, so we’ll keep a slight chance of rain in the Thursday forecast as well.

As a matter of fact, it looks like our area weather will remain modestly unsettled for Friday and the weekend -- we’re calling for rain chances at 20% to 30% for all three days. Now remember, that’s not a “washout” forecast for the weekend but it certainly doesn’t look like we can expect a repeat of the past weekend’s wonderful weather either.

So grab the umbrella on your way out the front door tomorrow!

Monday, April 22, 2013

Rains Return by Mid-Week
-- 22 April 2013

There was little to complain about with today’s weather: fair skies through the day and highs up around 80° with low humidity for many WAFB communities -- a nice spring day to follow-up on our outstanding weather weekend.
With today’s winds slowly swinging around to the east and southeast, Gulf moisture will slowly increase at the lower levels, reflected by the rise in dewpoints from the 40°s and 50°s over the weekend to the low 60°s by tonight into Tuesday morning. That means Baton Rouge lows tonight will only drop to the low 60°s compared to the chilly mornings on Saturday (39°, a record low) and Sunday (44°). We may even see a few patches of fog for Tuesday morning, but not enough to be an issue for the morning commute.
Highs return to the 80°s for Tuesday afternoon under a mix of sun and clouds. We could see a blip or two on Titan9 Doppler radar on Tuesday afternoon, but most WAFB neighborhoods will stay through the day and evening.

 A storm system currently located well to the northwest of Louisiana will drive a cold front into the Southern Plains by Tuesday afternoon, with the front draped through Arkansas and East Texas by Tuesday afternoon and evening. The front should be stretched from NE to SW across portions of Louisiana by Wednesday morning, moving into the WAFB viewing area by Wednesday afternoon, and continuing to head out to the Gulf coastal waters by day’s end.
While the latest projections from the NWS Weather Prediction Center (WPC) call for WAFB area rains on the order of 0.5” to 1.0” for Wednesday, the NWS Storm Prediction Center (SPC) has not issued any “RISK” potential for the lower Mississippi Valley at this time. Remember, that does not exclude the possibility of active to severe storms, but suggests that there is little if any threat for a widespread severe weather event on Wednesday. (Still, we’ll keep an eye on the potential over the next two days.)
Unfortunately, the latest guidance suggests that the front will slow and possibly stall near the coast late Wednesday into Thursday, and that could keep our weather modestly unsettled for Thursday and possibly even Friday. Highs both days look to top-out in the 70°s.
Into the extended outlook, a storm system is currently projected to develop over the Southern Plains on Friday into Saturday. It could drag another cool front through the state late Saturday or early Sunday but, admittedly, the extended models are a bit mixed as to what to make of this scenario. For the time being, we’ll go with scattered showers for both days and wait for the weekend forecast to come into better focus. Next Monday looks good.

Friday, April 19, 2013

Record Lows Likely Saturday Morning!

By Jay Grymes & Steve Caparotta

Temps fell into the upper 40°s for metro BR during the morning, thanks in part to the overnight front pushing through metro BR before midnight and the rains ending a little sooner than expected. Clouds hung around into the afternoon for much of the greater Baton Rouge area, with radar indicating some showers along the coast.

Those persistent clouds and the northwesterly wind kept the air quite cool into mid-day, but thankfully, the Capital City began seeing some peeks of sunshine by the lunch hour which allowed temps to climb into the 60°s during the afternoon. Yet even with that modest warm-up, it was nothing like the mid to upper 80°s over recent days.

Our forecast calls for clear skies with little or no wind combining with the very dry air mass in place overnight and early Saturday. That should set the stage for Baton Rouge to drop to a record low on Saturday morning! We’re calling for lows in the upper 30°s for the ‘Red Stick,’ with some WAFB communities up along the LA/MS state line dropping into the mid 30°s.

(For the trivia buffs: long-term Baton Rouge temperature record shows no readings ever as low as the 30°s this late in the month. In fact, a quick look at the available records suggests that temps at Baton Rouge have only fallen into the 30°s after April 15th on just four occasions -- prior to tomorrow morning.)

After a cold start for Saturday, sunshine will warm most of us into the low 70°s. We’ll have another chilly start for Sunday morning, but Sunday afternoon looks like another springtime weather winner, with highs in the mid to upper 70°s -- just about perfect for BR’s downtown Earth Day festivities!

The warming trend continues into Monday and Tuesday, with rain chances rising late Tuesday as our next cold front approaches. The current projections next week’s front have the boundary draped across central Louisiana early Wednesday morning with the system sweeping quickly out into the Gulf during the day. That should leave us with mild and dry weather for Thursday and Friday.

Enjoy the weekend weather -- and don’t forget the sunscreen!

Thursday, April 18, 2013

Turning Cooler on Friday!

By Jay Grymes & Steve Caparotta

A busy day weatherwise for Thursday: mostly cloudy, warm and muggy, with winds sustained above 20 mph and gusts into the 30s for much of the afternoon.  And that’s not all -- rains will be rolling into the viewing area later this evening with showers and t-storms on the ‘weather menu’ through the overnight hours.
As of 3PM, an east-bound cold front had already passed through Shreveport and Natchitoches.  The front was moving to the east at about 20 mph -- at that rate, it would be over the Baton Rouge metro area before midnight.

Also as of 3PM, the NWS had a Tornado Watch in effect (until 11PM) to the north of the WAFB viewing area, extending from NE Louisiana into western and central Mississippi.  A series of Tornado and T-Storm Warnings were issued along and just ahead of the front in the Watch zone.
Although the severe storms are currently well to the north, there remains a “SLIGHT RISK” for severe weather in the WAFB viewing area later tonight and early tomorrow according to the NWS Storm Prediction Center.  As is currently true north of us, any Warnings that are issued tonight for the WAFB region will be prompted by t-storms just ahead of the front, and once the front passes the threat will effectively come to an end.  The primary threat will be damaging winds; hail and a tornado or two, although unlikely, cannot be completely ruled out.
Current rain-total projections are running in the 0.5” to 1.0” range for most WAFB communities.
While we expect the front to move through BR metro area by or before midnight, the clear-out behind the front looks like it will take some time.  We’ll have to watch the weather trend through the evening and overnight as our guidance models are still not in complete agreement in terms of post-frontal weather.  For now, we’re anticipating clouds for the viewing area at sunrise with a few “backside” (post-frontal) showers.  The rains should come to a complete end for metro BR by mid to late morning (ending later to the east of Baton Rouge) with clearing underway through the afternoon as a cool and very-dry air mass takes charge.

Did we say cool?  How about cold -- at least by mid-April standards.  Our current forecasted low for Saturday morning is 40°, which would tie the record for the day (April 20th).  And we’ll have another morning in the 40°s for Sunday too!  The weekend is looking like a real beauty -- after the chilly starts, we’ll climb into the 70°s under sunshine for both Saturday and Sunday afternoon, with low humidity in place.  Sunday’s Earth Day celebration in downtown BR should be a big winner!

Into the extended outlook, our next cool front and rain chance arrives during the latter half of Tuesday into Wednesday.

Wednesday, April 17, 2013

Showers, T-Storms Late Thursday

By Jay Grymes & Steve Caparotta

Breezy and muggy conditions under mostly cloudy skies was the rule again today for the WAFB viewing area, and don’t expect any big changes in the coming 12 to 24 hours.  We did see a few blips on Titan9 Doppler radar this afternoon, but those should fade away later in the evening.
We’ll stay under mostly cloudy skies through the night and into Thursday morning, with another muggy start at or above 70° for the Capital City.  And like last night, the winds will stay sufficiently active to minimize any serious fog threat even with the humid air mass in place.
The weather does start a significant change-up later on Thursday evening and into Friday as our next cold front pushes across the Bayou State.  Timing of the first rains on Thursday remains a bit up in the air – for now we’re going with a 30% rain chance for Thursday afternoon and early evening with rain chances rising rapidly later into the evening and overnight.

The NWS Storm Prediction Center posts a “SLIGHT RISK” for severe weather during the overnight and early morning hours (Thursday into Friday) for just about the entire WAFB viewing area, with the threat mainly in the form of damaging winds.  In addition, the latest NWS projections call for 0.5” to 1.0” of rain for most WAFB communities.

What is a bit disappointing is that the latest runs from our in-house RPM model and the European model continue to keep clouds and even some lingering “backside” rains (overrunning rains, behind the surface front) well into Friday afternoon.  So the clear-out will be somewhat slow at best, but you will notice the difference after the front moves through in the morning.  After highs in the 80°s for each of the past three days, most of us won’t get out of the 60°s on Friday afternoon!  With luck, the rains will be gone before “Live After Five” … but it will be noticeably cooler for the 5-8 pm window compared to recent Fridays.
The weekend shapes up to be nearly perfect: low humidity, cool mornings with sunrise temps in the 40°s and afternoons under sunny skies with highs in the 70°s.  Make some outdoor plans -- and grab the sunscreen!

Temps will rebound to around 80° for next Monday and Tuesday, with our next cool front currently scheduled to arrive at mid-week.

Tuesday, April 16, 2013

Breezy, Warm & Muggy Weather Continues

By Jay Grymes & Steve Caparotta

A few light showers overnight, patches of fog for the morning, then persistent clouds and a muggy air mass -- that pretty much shapes up the past 18 to 24 hours.  That will also be close to the forecast for tonight and Wednesday.
We don’t expect the “surprise” showers we had late last night, although a few still could see a sprinkle or two this evening.  In addition, we’ll add an ever-so-slight increase in rain chances for Wednesday afternoon -- at 20% or less.  The winds will return on Wednesday with a steady flow off the Gulf in the 10 to 20 mph range.  It will be another muggy day on the way with highs returning to the 80°s for just about everyone in the viewing area.
The outlook for Thursday morning and afternoon are shaping up to be a near carbon-copy of our Wednesday forecast, with changes arriving late Thursday night into Friday morning.
An upper-level low over the western U.S. will continue a slow march to the east, cutting across the Central Plains on Wednesday and Thursday on its way to the Great Lakes.  That system will drag a cold front into the lower Mississippi Valley late Thursday into Friday. 
At this time, the NWS forecast calls for rain totals running from 0.25” to about 1.00” for the WAFB viewing area with locally-higher totals.  The Storm Prediction Center also has metro Baton Rouge on the edge of an area outlined under a 'slight risk' of severe weather late Thursday into Friday morning. We're seeing mixed signals on the threat of severe weather, so we'll take another look at that on Wednesday.

Friday’s afternoon forecast remains in question.  While Friday’s cold front is currently expected to be moving to the east and out of southeast Louisiana in the early morning, our in-house RPM model and the rather-reliable European model suggest some “backside” showers and clouds could linger into the latter half of the day.  We’ll watch over the coming days to see how that shakes out.

But here’s the good news -- we get the wet weather out of here on Friday, leaving us with an outstanding weekend ahead.  Look for sunny skies for both Saturday and Sunday, with cooler and drier air in place both days: sun-up temps in the 40°s and afternoon highs in the 70°s!  It’s looking superb for Sunday’s Earth Day festivities.

Monday, April 15, 2013

Areas of Fog Next Few Mornings

** Dense Fog Advisory in effect from 10 PM tonight through 10 AM on Tuesday **

Fog will continue to be our primary weather concern over the next few days. Visibilities only got as low as 6 miles at metro Baton Rouge this morning, but many other locations reported visibilities under a quarter-mile. While winds will stay in the 5-10 mph range overnight, the threat of dense fog will be returning, so be alert for reduced visibilities if you’ll be driving late tonight or on Tuesday morning.

Otherwise, Tuesday and Wednesday are shaping up to be quite similar to today. Look for mostly cloudy skies, breezy and warm weather, along with a slight chance of a sprinkle or shower. Depending on the amount of sunshine in your neighborhood, highs will likely range from the low to mid 80°s.

Good rain chances will arrive late in the week as our next cool front moves in from the west. Widespread showers and t-storms are expected late Thursday night into Friday morning as the front moves through. Early indications point toward at least some threat of severe weather as well.

The good news is that skies should clear by Friday afternoon and give way to a beautiful weekend. Somewhat cooler and less humid weather is expected for a few days, with lows dipping into the 40°s over the weekend and highs topping out in the low-mid 70°s.

Friday, April 12, 2013

Another Beauty on Saturday!

By Jay Grymes & Steve Caparotta

You’ll certainly have a tough time trying to find something disagreeable with today’s weather and we think the same will be true for Saturday.  We’ll begin Saturday under clear skies with sunrise temps in the upper 40°s to near 50° for metro Baton Rouge.  By the afternoon, southeast winds will help warm the day a bit more than Friday -- we’re expecting highs in the upper 70°s to around 80° for the ‘Red Stick’ under mostly sunny skies.  The afternoon will be occasionally breezy, with winds running from 5 to sometimes 15 mph. Overall, it looks just about perfect for Blues Fest in downtown Baton Rouge.

Saturday will be the weekend “get outdoors!” day ... as Sunday is shaping up to be a wet one.
As we noted yesterday, our Sunday forecast calls for a warm front over the Gulf to move into coastal Louisiana by Sunday morning.  The first rains could begin impacting the coastal parishes well before sunrise on Sunday, and it looks like metro BR and areas north of the Capital City should expect scattered showers and a few t-storms during the morning and potentially into the afternoon.  For the time being, there does not appear to be a serious “severe weather” concern, but some WAFB communities could see 1” or rain or more under the stronger t-storms.

The weather will be quieter, but not necessarily rain-free for Monday, Tuesday and Wednesday, with afternoon temps running in the mid 80°s for all three days.

Rain chances take a big jump up on Thursday as our next cold front slides through the region.  But that should leave us with another great Friday to end NEXT week!

Thursday, April 11, 2013

A Couple of Nice Days Ahead!

By Jay Grymes & Steve Caparotta

The rain and storms were slow to arrive this morning, but once they did, the rains were rather intense for about an hour for many of us.  At Metro Airport, the temperature dropped from the day’s high of 75° to the day’s low of 54° in less than 90 minutes as the surface front moved through, with the heaviest rains and storms behind the front rather than ahead of it.
Fortunately, while the WAFB area was under a Tornado Watch for much of the morning, there were no reports of weather-related damage in the greater metro area.  However, the storms appeared to intensify after they moved east of metro BR, and there were several reports of wind damage in Washington and St. Tammany parishes as well as at least one confirmed tornado touchdown on the northwest side of Slidell.

Rain totals for most WAFB neighborhoods were in the 0.5” to 1.0” range.  A few sites reported larger totals, while communities closer to the coast tended to report lesser amounts.

While we are done with that weather, the line of storms continue to produce damage and heavy rains as it marches farther east this afternoon and evening.  For us, the clearing is well underway.
With a cooler-and-less-humid air mass in place, we can expect a couple of “almost chilly” mornings for Friday and Saturday, with sunrise temps in the 40°s!  But both afternoons will be real beauties too, with highs in the 70°s, very low humidity and lots of sunshine -- looking good for Friday’s Live After Five, Saturday’s Baton Rouge Blues Fest, and just about anything you can think of to do outdoors on a Friday or Saturday.

Unfortunately, it won’t be a perfect weekend, as rain returns to the outlook for Sunday.  A warm front advancing northward across the Gulf will provide the stimulus for scattered showers and a few t-storms on Sunday and may still have an impact into Monday.  Although not entirely dry, our regional weather should settle down somewhat on Tuesday into Wednesday before the next advancing front produced another chance for widespread rains on Thursday.

Wednesday, April 10, 2013

Strong Storms Possible Thursday Morning

Windy and warm conditions prevailed across the WAFB viewing area today, with highs once again climbing into the mid 80°s despite a good deal of cloud cover this afternoon. Radar has been fairly quiet most of the day, but that will begin to change late tonight.

A cool front in east Texas as of late afternoon is making slow progress toward Louisiana. Showers and t-storms, some severe, have begun to line up along the front out to our west. So far, the most significant severe weather has been up to our north.

A few spotty showers are possible this evening, but rain chances will begin to increase after midnight as the front inches closer. By the time you wake up on Thursday morning, showers and t-storms will be fairly widespread, especially from Baton Rouge westward. Rains will gradually spread eastward as the morning progresses.

We have two main concerns headed into Thursday morning: 1) the threat of severe weather, and 2) the potential for locally heavy rains. While it does look like severe weather will be most widespread to our north, a few strong storms primarily capable of producing damaging winds will be possible. As for the rains…totals of 1” to 2” will be common in our viewing area, but isolated amounts of 3”+ are possible.

The wet weather should come to an end from west-to-east during the afternoon as the cool front slides to our east. In fact, we may even squeeze out a little sunshine before the day is up.

Big improvements are expected in our weather by Friday. That means for the second week in a row, it should be just about perfect for Live After Five on Friday evening. And the weather looks equally nice for Saturday’s Baton Rouge Blues Fest to be held downtown.

Scattered showers and t-storms return to the forecast by Sunday, with isolated-to-scattered rains in the forecast each day through much of next week.

And as a not-so-gentle reminder that Hurricane Season is just around the corner, the team at Colorado State led by Dr. William Gray & Dr. Phil Klotzback released their forecast for the 2013 Atlantic hurricane season today. The team is predicting 18 named storms, 9 hurricanes, and 4 ‘major’ (Category 3 or stronger) hurricanes…numbers that are significantly above-normal. Using another metric from the team called ‘Net Tropical Cyclone Activity’ (NTC), they forecast tropical activity to be nearly 75% above-normal in 2013. Among the factors pointing to an active season are warmer-than-normal waters over a large part of the Atlantic, low wind shear, and the expectation that an El Niño will NOT develop. Remember, El Niño events tend to produce increased wind shear in the Atlantic, something that serves to reduce tropical activity.

Obviously, these forecasts must be used with great caution and as we always remind you, it only takes one ‘healthy’ storm to make it an active season locally. Let this serve as a reminder to start stocking up on hurricane supplies and make sure your families and homes are ready for the upcoming season…

Tuesday, April 9, 2013

Windy, A Few T-Showers on Wednesday

By Jay Grymes & Steve Caparotta

Even with the clouds and steady winds, we had an “almost summer” feel to the air this afternoon, with high humidity thanks to the southerly winds delivering a steady flow of moist Gulf air.  In addition, most WAFB neighborhoods saw afternoon temps rise into the low to mid 80°s -- not uncommon for this time of year, but certainly adding to the warm and muggy feel for the afternoon. Today's high of 87° in Baton Rouge makes it our warmest day since Oct. 5th of last year!

The clouds stay with us through the evening and overnight, and while the winds will back down a bit, the steady flow of Gulf moisture will continue tonight and through the day on Wednesday.  As was true for Tuesday morning, we’ll start Wednesday on the warm-and-muggy side, with sunrise temps around 70° for many of us.  And as we saw on Tuesday morning, we’ll have patches of mainly-light fog in the area, but the winds should be sufficient to minimize any real fog-related concerns for commuters.
By mid-day, steady southerly winds like those we experienced today will return, again in the 10 to 20 mph range for much of the day with gusts in the upper 20s and 30s!  And highs for Wednesday will return to the 80°s too.
We’re still watching the storm system to our northwest, currently strengthening as it spins over the Central Plains.  As we mentioned yesterday, the core of this storm will track to the east and will remain well to our north, but its trailing cold front will sweep through the Southern Plains tonight and early tomorrow and then trek across the lower Mississippi Valley late tomorrow into Thursday.
The timing of its approach and passage through the WAFB viewing area still varies by a handful of hours between some of the operational models, but they all are calling for a very wet first half of the day for Thursday across WAFB parishes and counties.  The biggest differences appear to be just how long the rains might linger into Thursday afternoon and evening.

It’s looking like the front will slow its forward progress as it moves across Louisiana and that could mean some significant rain totals.  We’re anticipating fairly widespread event totals of 1” to 2” or more, with pockets possibly topping 3” over the period between Wednesday evening and Thursday afternoon.  In addition, the entire WAFB viewing area remains posted under a “Slight Risk” for severe storms, mainly in the window between midnight and roughly 8AM or so on Thursday.
Our Titan9 RPM model projects 1" to 2" of rainfall for much of the area through Thursday, with localized  amounts in the 2" to 3" range.
The clearing will be slow on Thursday afternoon and evening, but that should leave us with a very nice Friday and Saturday.  Sunday still is still a weather question mark, however, as several models hint at a weak disturbance tracking across the northern Gulf and potentially delivering scattered rains to our viewing area on Sunday into Monday.

Monday, April 8, 2013

Windy & Warm on Tuesday!

By Jay Grymes & Steve Caparotta

While it has been a dry day for the WAFB viewing area, we have been tracking showers -- and an embedded t-storm or two -- moving from southwest-to-northeast through Central Louisiana.  There is also some action offshore to the south of Cameron and Vermillion parishes, and these may need to be watched into the evening for our friends in Acadiana.  Yet, even though it’s been a fairly nice day across WAFB country, you’ve probably noticed the breezes through much of the afternoon.  Our forecast calls for it to get even windier for Tuesday, with winds lingering into Wednesday as well.

We opened Monday with some patches of fog around our area, enough along the Mississippi River to shutdown the Carville ferry for a while this morning.  Fog is expected to return for Tuesday and Wednesday mornings, but we think that the winds will be sufficient to keep fog from becoming a widespread problem for either morning commute.  But if you travel through those “usual suspect” spots for morning fog, be on the look-out both days.

As for Tuesday, we can’t rule out a spotty shower during the day, but we think that it will be a “mainly-dry” and windy afternoon.  Highs will get into the low 80°s even under a mostly-cloudy sky and you’ll likely “feel” an increase in low-level humidity during the day as Gulf moisture gets pumped into the Gulf Coast region.

Our forecast for Wednesday and Thursday makes rain a near-certainty, but there are still some issues regarding the timing of the rains.  A storm system currently rolling through the Central Rockies will get better organized once it clears the mountains and sets-up over the Plains.  At the same time, we’ll see winds pick up thanks to a steep pressure gradient, with the Plains low-pressure system to our northwest and a large ridge of high pressure to our northeast, just off the U.S. Atlantic Coast.  That pressure gradient will set-up steady and sometimes strong southerly winds over the next two days.

A frontal system associated with the Plains low will track eastward, bringing us rain and a threat for severe weather on Wednesday and into Thursday.

While the computer guidance models are not in total agreement today, the consensus opinion is that an advancing cold front reaches the ArkLaTex area by Wednesday morning and will be draped over the WAFB viewing area by Thursday’s sunrise.  The NWS Storm Prediction Center has the WAFB area under a “Slight Risk” of severe weather -- mainly strong winds -- for the period extending from the latter half of Wednesday into Thursday morning as the front approaches and passes by. 

The weather should start improving during the latter half of Thursday, with great spring days on tap for Friday and Saturday.

Unfortunately, there is some question as to whether Sunday will follow suit: at least one model hints at a disturbance moving along or near the Gulf Coast on Sunday into Monday.  We’ll watch the extended range forecasts over the coming days to see if the forecast models continue with this scenario.

In the meantime, it’ll be umbrellas for Wednesday into Thursday ... and sunscreen for Friday and Saturday!

Friday, April 5, 2013

Enjoy the Sunshine This Weekend!

If you were with me at 9 or 10 last night, I mentioned that clouds would probably be a bit slow to exit this morning…and indeed that was the case. But wasn’t it nice once the sun finally broke through this afternoon?!

The afternoon sunshine translated into temps running 10° - 15° warmer than yesterday when we were socked in with clouds. Highs in the mid to upper 60°s for most WAFB neighborhoods are still about 10° below-normal for the date, but they mark the beginning of a warm-up that will continue into the weekend.

Saturday still gets off to a somewhat cool start in the upper 40°s under mainly clear skies, but afternoon readings will rebound into the mid 70°s under mostly sunny skies. So it looks just about perfect for ‘Zippity Zoo Fest’ at BREC’s Baton Rouge Zoo or anything you may want to get done outdoors!

Returning southerly winds this weekend will transport increasing amounts of Gulf moisture into the area. That will translate into the likelihood of some low clouds on Sunday morning, but winds may stay just strong enough to prevent significant ground-level fog. We’ll keep an eye on it. And after perhaps a mostly cloudy start on Sunday, clouds should break and give way to a good deal of sunshine by the afternoon, with highs reaching the upper 70°s.

The extended outlook points toward warm weather through at least the mid portion of next week. Right now, Monday and Tuesday appear to stay mainly dry, but better rain chances return Wednesday and/or Thursday. We’re fairly confident that at least one of those two days will see a good coverage of showers and t-storms, but not real sure of which one will be wettest just yet. One of our longer range models points toward a cool front moving through on Wednesday, while another is a full day later with the front moving through on Thursday. We’ll fine-tune the details as the event gets closer.

Enjoy the beautiful spring weather and have a great weekend!