Tuesday, September 16, 2014

Less Rainfall on Wednesday

By Jay Grymes & Steve Caparotta

WAFB First Alert Quickcast:

- scattered rains for Wednesday & Thursday
- ‘drier’ for Friday and Saturday
- Edouard becomes the season’s first ‘major’ hurricane
We had to wait until about 1:00pm, but as predicted yesterday, the rains arrived for most WAFB neighborhoods this afternoon.  Radar trends suggest two features at work today: a northbound “sea breeze” front and a southward-sagging band of showers and storms that extended along a west-to-east line from Avoyelles and St. Landry parishes into the eastern Florida Parishes.  Although none of the storms proved ‘severe’, a number were highly-charged with frequent cloud-to-ground lightning, produced locally-heavy downpours and generated some noteworthy wind gusts.  We even received a report of small hail during the early afternoon from the Springfield area (Livingston Parish).
Heavy downpours prompted the NWS to issue a FLASH FLOOD WARNING from approximately 4:00-5:45pm for portions of Ascension, Assumption, Iberville and St. James parishes.
This activity will taper-off into the evening hours, but we expect to see lingering showers -- and possibly a storm or two -- into the late evening.  We’ll carry spotty showers into the Wednesday morning forecast, mainly for areas closer to the coast.  Look for Wednesday sunrise temperatures in the low 70°s for metro Baton Rouge with some pockets of mainly-light fog to accompany the AM commute. 
We expect some rain for Wednesday afternoon but with the percentages set at only 30% -- not the widespread activity like we saw today.  Plan on a sun/cloud mix through the afternoon with temperatures getting up into the low 90°s for many WAFB communities.
Thursday starts with spotty morning showers again and lows in the low 70°s for the Red Stick.  Set afternoon rain chances for Thursday at 30% to 40% with highs in the upper 80°s to around 90° for most WAFB communities.
The fact is, the entire forecast for the next several days remains a little unclear.  We continue to struggle with defining the forecast positions in the next few days of a cool front that separates the warm-and-muggy Gulf air mass currently over us from a cooler-and-less-humid air mass to the north.  Our current thinking has the front meandering somewhere over Louisiana through Thursday before finally sagging south towards the Gulf on Friday. 
Our Friday forecast shapes up to be a pretty good one as does the outlook for Saturday: fair to partly cloudy skies with isolated showers for both days.  Depending on the front’s position, both days could be essentially rain-free with a nice dip in the humidity -- but we’ll have to wait another day or so to see how this pans out.
After that, our next cool front begins to approach south Louisiana from the Plains on Sunday -- guidance suggests that it reaches the state sometime on Monday.  We’ll call for a 30% rain chance for Sunday as the air mass ahead of the front becomes more and more unstable, then go with a 50-50 rain chance or better for Monday. 
Could next week’s front be that “first fall front” suggesting an end to summer heat?  It’s possible, but let’s wait a couple of days to see if next week’s weather picture comes into better focus before we start celebrating!
In the open Atlantic, Edouard was upgraded to a ‘major’ hurricane (Category 3) as of 10:00am this morning -- not just the first ‘major’ hurricane of 2014 but the first ‘major’ since 2012’s Sandy.  But Edouard has already weakened and been downgraded as of 4:00pm to Category 2.  Beyond that, there are no significant changes to the basic track forecast for Edouard, with the system expected to turn more to the NE and stay over the ocean.  The latest forecast suggests that Edouard will continue to slowly weaken but could hold on to hurricane strength into Thursday before succumbing to the cooler waters of the north-central Atlantic.

Monday, September 15, 2014

Good Rain Chances on Tuesday

By Jay Grymes & Steve Caparotta

WAFB First Alert Quickcast:

- a ‘wet’ Tuesday likely for the WAFB area
- no tropical threats for the Gulf region any time soon

We had a 2” downpour here at the WAFB studio earlier this afternoon, most of it falling between about 1:30-2:30pm. While radar was ‘lit up’ around the immediate metro area from about 1:00-3;00pm, the majority of WAFB communities managed to stay dry through the day. However, as of 4pm, we’re still tracking some action, especially south of the Capital City. The atmosphere across our viewing area remains rather juicy, so we’ll keep spotty showers in the overnight and morning forecast. That means “mostly dry” for the morning drive and school bus ride on Tuesday, with lows around sunrise in the low 70°s for metro BR. 

Rain chances will increase as the day progresses, so the question becomes: “Just how widespread will it be?”

We admit to getting mixed signals from the models on the rain coverage for Tuesday, with rain percentages running from roughly 40% to as high as 80%. We’ll split the difference for now and call it 60% or so for the afternoon -- in other words, “showers & t-storms likely.” The rain and clouds should keep Tuesday’s highs in the mid to upper 80°s for just about everyone, with the rains tapering off into the evening. We’re carrying spotty showers in the late Tuesday night/Wednesday morning forecast with rain chances rising to about 40% for Wednesday afternoon.

A frontal system to our north is headed our way and appears that it reaches the WAFB area on Wednesday – plan for scattered showers and storms for Wednesday afternoon. The front may slow a bit as it continues south and again the model guidance isn’t in agreement as to what happens for Thursday and Friday. For the time being, we’ll set rain chances at 30% for Thursday and 20% for Friday, but we do so with somewhat low confidence. If the front can push far enough south, both days could become fair-weather days.

Expect lows near 70° to the low 70°s for metro BR just about all week long, with highs in the upper 80°s to near 90°. Headed into the weekend, we’ll call for 30% rain chances for both Saturday and Sunday, with highs in the upper 80°s to near 90°. And in the extended, the guidance is hinting at another cool front early next week.

We’re still tracking a very strong ‘Category 2’ Edouard, moving NW to NNW over the open Atlantic. The latest NHC forecast calls for Edouard to continue to intensify, becoming a Category 3 hurricane later today or tomorrow - - the first ‘major’ hurricane of the 2014 season. Fortunately, Edouard will remain well to the east of Bermuda, which means no threats to land as we await the expected turn to the north and then NE. Meanwhile, in the eastern Pacific Basin, Hurricane Odile continues to spin over the Baja (California) Peninsula and is expected to remain over land for the next day or so. Remnants of Odile (likely a depression by or before Wednesday) could reach the U.S. Southwest later in the week.

Thursday, September 11, 2014

Scattered Rains into the Weekend

By Jay Grymes & Steve Caparotta

WAFB First Alert Quickcast:
- even better rain chances for Friday & Saturday
- a new Tropical Depression … and watching the invest to the east of Florida
Our run of mostly-dry days has ended.  Scattered rains this afternoon will give way to even greater coverage tomorrow as the cool front we’ve been talking about makes its way into northern Louisiana then slows to a crawl.
With the front drawing closer and a steady inflow of moisture off the Gulf, we’ve got the set-up for a rather wet Friday afternoon: not the best news for Baton Rouge’s ‘Live After Five’ nor area high school football.  While Friday will start-off mainly dry, we’ll go with scattered-to-likely showers and storms for Friday afternoon (50% or so).  And unfortunately, scattered rains linger into the evening hours too.
Set sunrise temps for Friday in the low to mid 70°s for metro Baton Rouge under partly cloudy skies.  As we’ve seen just about all week, we could see a few patches of mainly-light fog for the morning commute as well as a spotty shower or two, but it should be a mostly dry start to the day for just about all WAFB communities.  Temps for most neighborhoods will still reach around 90° or so during the day before the clouds and rains kick-in.
Saturday?  Not much better.  In fact, we’re carrying isolated showers in Saturday’s morning forecast with roughly 50-50 rain chances for the afternoon.  The cool front over the state will slowly sag southward during the day, serving as a lifting mechanism to support rains.  However, clouds and rain should keep daytime highs in the 80°s for Saturday, but it won’t be a good day for pre-game tailgating for the Jags on the Bluff, around Death Valley for the Tiger faithful, nor down in the Crescent City for the SLU Lions. 
By Sunday, we think that the front will be meandering near the coast and over the coastal waters.  Backside clouds will still keep things mostly cloudy, but rain chances should drop a bit.  With a little luck, communities north of the I-10/12 could see lows slip into the upper 60°s by Sunday’s sunrise.  We’ll set rain chances for Sunday at about 40% -- greatest closer to the coast -- with highs again topping out in the upper 80°s to maybe near 90°, depending on how much sunshine your neighborhood gets.
For next week, we keep scattered mainly-afternoon rains in the forecast for just about every day.  Morning starts will be near 70° to the low 70°s and afternoon highs return to the upper 80°s to near 90° each day.  So we do expect a modest dip in the daytime temperatures compared to this week … but still nothing “fall like” in the short-range.
In the tropics, we’re watching two features.  Earlier today, the National Hurricane Center (NHC) upgraded Invest 91L to Tropical Depression #6.  The NHC forecast calls for T.D. #6 to become T.S. Edouard in the short term with the system potentially reaching hurricane status within the next five days.  However, the key to this tropical story is that whatever T.D. #6 becomes, it should remain over the open Atlantic and pose no threats to land.
Closer to home, we continue to watch the low-pressure ‘blob’ to the east of Florida, Invest 92L.  92L is looking rather ragged today, with its convection well-separated from the apparent low-level core due to persistent northeasterly shear.  What’s more, all indications are that the shear remains in play through the next couple of days, at least, as 92L slowly tracks to the west or WSW across the Florida peninsula.  That shear is a main reason why the NHC canceled the scheduled aircraft recon earlier today and why they are keeping development chances on the low side (only 30% through the next five days).
Virtually all of the model guidance has 92L moving into the eastern Gulf by Saturday morning … and that is getting everyone’s attention (as it should) … with several models taking the system towards the central Gulf Coast early next week.   However, most of the models are also indicating that the shear will continue to play havoc with the system and limit any real opportunity for intensification.
That said, we’ve seen it before: things can change in a hurry.  There is no need for concern at this point … we are far from any kind of serious threat.  However, with the weekend approaching, now is the time to evaluate your personal, family and business preparedness plans.  Get everything ready BEFORE a potential threat develops.
Want some help to get ready or fine-tune your current readiness?  It’s never too late to become better prepared.  Check out: 

Wednesday, September 10, 2014

Rains Returning to the Forecast

By Jay Grymes & Steve Caparotta

WAFB First Alert Quickcast:

- afternoon highs in the 90°s continue through Friday
- increasing rain chances from Thursday into the weekend
- no Louisiana threats in the tropics

Just about everyone stayed dry today as expected, with only brief spotty rains developing over the WAFB area. Look for any lingering activity to subside around sunset. We’ll stay dry again through the night and the morning, with mostly fair skies and a few patches of mainly-light fog for the Thursday morning commute. Sunrise temps for the Red Stick will be in the low to mid 70°s. For Thursday afternoon, the weak high-pressure lid on the atmosphere that kept most dry today weakens at tad, allowing for a little greater cloud coverage and ultimately a 20% to 30% coverage of showers with a few rumbles of thunder. Highs for Thursday will again reach the low 90°s -- and “feel like” 98° to 103° for many neighborhoods in terms of peak afternoon Heat Indices.

Unfortunately, there is no improvement in the wishful thinking of the approaching “cool” front: as we feared, the guidance is now suggesting that the front may not even make it as far Baton Rouge before Friday evening. And after that, it is expected to stall along or near the southern parishes for the weekend: so much for our hopes of a “taste of fall weather” for the weekend.

Friday starts out mainly-dry with sunrise temperatures in the low to mid 70°s. Highs for many WAFB communities will reach 90° or above for the afternoon, but we’re going with scattered showers and t-storms for Friday afternoon and evening -- not great news for this week’s downtown ‘Live After Five’ or Friday night high school football. But we do expect the rains to subside a bit as we head into the evening hours, so we can hope for a decent evening.

The front is then expected to slowly sag southward for Saturday and Sunday, serving as a rain enhancing feature for the weekend. Yes, highs will far short of the 90°s over the weekend for many WAFB communities, but the reason will be more about the clouds and rains than the result of a changing air mass as the front slowly slips by. Set rain chances for Saturday at 50% or better, then around 40% or so for Sunday.

LSU, Southern and Southeastern football fans will once again be encouraged to tote the rain gear for gameday festivities, especially for the pre-game tailgating. With a little luck -- like all three campuses had last week -- game time conditions should be at least a bit more agreeable.

The outlook through the first half of next week keeps scattered mainly-afternoon showers and t-storms in the regional forecast, with lows near 70° and highs in the upper 80°s to near 90° for Monday through Wednesday.

In the tropics, the National Hurricane Center (NHC) is still tracking Invest 91L in the east-central Atlantic. 91L hasn’t shown any real development over the past 24 hours but it still has some potential to become our next tropical cyclone (a depression or tropical storm) down the road - - the NHC currently posts 91L with a 70% chance for cyclone development in the next five days. Regardless, the early forecast guidance appears to keep 91L over the open Atlantic regardless of what development may transpire.

The NHC also upgraded the area of low pressure centered near the Bahamas: by “upgrade” we mean declaring it as an invest (Invest 92L). Development potential -- still posted at just 20% over the next five days as of 2PM -- is likely to be increased later this evening given the latest satellite presentations. Remember, when the NHC defines a disturbance as an “invest,” it sets more extensive tropical analyses into motion, not just with the NHC experts, but also with a number of supporting agencies and university research groups. Look for “spaghetti model plots” to begin arriving over the coming hours with the forecast consensus likely taking the system (whatever it becomes) into the eastern Gulf. Stay tuned …

Tuesday, September 2, 2014

Little Change This Week...

By Jay Grymes & Steve Caparotta

WAFB First Alert Quickcast:

- maintaining that summertime ‘fell’ through the week
- watching T.S. Dolly head towards Mexico
Taking care of the tropics first . . . T.S. Dolly continues to head towards The Mexican Gulf Coast and should make landfall sometime overnight or early in the morning.  Dolly could intensify a bit before landfall, but the forecast keeps ‘her’ as a moderate tropical storm when ‘she’ cross the coastline.  Dolly is the first ‘named’ storm of the 2014 season for the Gulf of Mexico ... and the first ‘named’ storm of 2014 not to reach hurricane strength.  Elsewhere in the Atlantic Basin, there are no areas of immediate concern.
Back closer to home, it may be a new month but it still feels like summer.  But remember, it is supposed to, especially in the Deep South.  Summer doesn’t officially end for almost another three weeks (on Sep 22), and it is not rare to have some hot days in the first half of the month.  In fact, the longest consecutive stretch of 100° days for Baton Rouge occurred from August 20 to September 5 (7 days) back in 2000 - - there is no other run of more than 4 consecutive days at 100° or more, at least since 1930.
We’re not expecting much of a chance in our outlook for the rest of the week and into the weekend.  If anything, it may get a little ‘wetter’ than what we saw today.  We’re going with rain chances at around 40% t0 50% each day right into next Monday - - with most of the rain being the summertime afternoon variety.  And in keeping with the summer season, morning lows wil be in the low to mid 70°s for the Red Stick with afternoon highs in the low 90°s.
Bottom line: no relief from the summer heat just yet.
But this is a transition month -- no doubt about it – as Baton Rouge normals take a big step down during the four week period.  While normal highs at the start of September are in the low 90°s, they drop to the mid 80°s by month’s end.  And the daily low normals slip from summer-like low 70°s down to comfortable mid 60°s.  Yet maybe the biggest weather story in most Septembers is the welcomed arrival of the first real autumn front.  (Okay, that is the biggest September weather story as long as the tropics are behaving.)
So keep the A/C on high for now .. and with some weather luck, we’ll have a run of days in the coming months when we can shut it off and open the windows!

Thursday, August 28, 2014

Good Rain Chances for the Holiday Weekend

By Jay Grymes & Steve Caparotta

WAFB First Alert Quickcast:

- Scattered rains for Friday afternoon, wetter for Saturday & Sunday 
- still waiting for 98L to move inland into Texas

We’ll start with a look again at 98L, that area of disturbed weather spinning east of Brownsville. It has been slow to move but appears to have finally moved onto the Texas coast as of the mid-afternoon. Although we’re still seeing some storms associated with it over the western Gulf, development chances for a tropical cyclone now appear to be “zero.” However, given the time of year and the warm Gulf waters, we’re not ready to declare 98L officially dead until it is fully inland later this evening.

It has been another mostly-dry day for the WAFB viewing area with rain activity occurring well to our west. However, an east-to-SE flow has become re-established over the viewing area today, bringing in more Gulf moisture. The enhanced humidity, working with daytime heating, popped a few afternoon showers and t-storms, but today’s sun/cloud mix helped slow the mid-day warm-up. What rain is out there this afternoon will subside into the evening, with partly-to-mostly cloudy skies expected overnight and into Friday morning.

Friday’s morning commute should be a dry one -- with the exception of a possible shower or two closer to the coast. Plan on Red Stick temperatures in the mid 70°s around sunrise. Temperatures should climb to 90° or above for most WAFB neighborhoods before Friday’s scattered afternoon showers and t-storms knock back the daytime heat. We’re calling for a 50-50 rain chance on Friday afternoon for the viewing area -- so be ready to hit some pockets of rain during the Friday evening drive home. 

Friday’s rains will again subside into the evening, but we’re going to carry isolated rains in the overnight and early Saturday outlook. By mid-day Saturday, we’re going with widespread rains for our forecast, setting Saturday’s rain chances at 70% or better. These probably won’t be all-day continuous rains, but be ready for on-and-off showers and storms throughout the better part of the day. Saturday’s wet weather should keep daytime highs in the 80°s rather than the 90°s. unfortunately, the next day doesn’t look a whole lot drier either: we’re calling for a 60% rain on Sunday with highs near 90°.

For Monday, Labor Day, we’ll ease back on the rain chances to around 40% -- an improvement over the weekend numbers but still the scattered afternoon variety of Louisiana summer weather. And for next week’s Tuesday-thru-Thursday window, we’re keeping rain chances in the 30% to 40% range for each day.

Elsewhere, ‘Category 1’ Cristobal shows no signs of weakening just yet; in fact, there remains a chance that Cristobal could actually get a little stronger before ‘he’ finally begins his transition to a non-tropical system in the North Atlantic. We’re still watching a broad west-to-east oriented low-pressure belt stretching from the central Caribbean to the tropical Atlantic east of the Lesser Antilles. While there is no imminent threat for development, this area needs to be watched as it moves to the west in the coming days. Some of our computer guidance is hinting at potential development early next week over the western Caribbean or southern Gulf. And lastly, although the NHC experts are less “bullish” about it than they were just a day or two ago, they are still watching a tropical wave about to enter the eastern Atlantic off of West Africa.

And then there’s football.

For south Louisiana high schools, be ready for a little rain during Friday night’s jamborees, although we expect the showers to steadily subside through the evening. As for Saturday’s big college contests in Houston, Lafayette and Hammond, afternoon tailgaters will want to have the rain-gear on the ready wherever they are. For the Tigers in Houston against Wisconsin, the good news is that the ‘lid’ will be closed on Reliant Stadium for the match-up with Wisconsin (8pm kick-off). But for the Jaguar Nation visiting ULL in Acadiana (6pm) and for the SLU Lions fans enjoying their home opener at Strawberry Field (7pm), scattered rains are likely to still be dotting the south Louisiana landscape at “first whistle” and lingering for much of the respective first halves.

Wednesday, August 27, 2014

Rains Returning to the Forecast

By Jay Grymes & Steve Caparotta

WAFB First Alert Quickcast:
- rain chances rising into the weekend
- still eyeing the disturbance in the western Gulf

For most of us, today was another relatively quiet weather day, with a prolonged run of NE to easterly breezes thanks to the circulation around the low-pressure area in the Gulf. After a morning start in the low 70°s for the Red Stick, most WAFB neighborhoods climbed into the low 90°s for the afternoon, but rains were fairly limited and the humidity was quite tolerable for an August day.

Of course, most of the local weather attention remains focused in the western Gulf. Admittedly, the area of low pressure tried to ‘kick up its heels’ overnight with another round of convection popping up in the early morning. The low-level circulation was (and is still) evident, but throughout most of today the main storm energy with this system remained to the north and east of the low-level spin. As of this afternoon, the National Hurricane Center (NHC) remains unimpressed with the disturbance -- listing it with only a 20% chance for development in the next two days. However, the NHC did concede that it deserves attention, dubbing it “Invest 98L” and scheduling today’s visit by aircraft. 

So, the real question for 98L: will it stay out over the water long enough to get its act together and earn tropical cyclone classification (as a depression or tropical storm)?

Well, there is no question that the Gulf is ‘warm’ enough to support intensification and the mid-level shear has appeared to relax a little today. Given the time of year, we won’t rule out a brief upgrade to depression strength, especially if 98L slows its westward movement. However, “space is limited” for the system -- if it doesn’t slow to a crawl or stall soon, it will be over the Texas coast before you know it. Regardless, high pressure to our north should keep 98L well to our south and southwest and west-bound into Texas. And for “droughty” central Texas, a dose of tropical rains would be welcomed.

For us, the drier pattern we’ve enjoyed is coming to a quick end. Winds will start to swing back around from the SE by mid-day Thursday, pumping Gulf moisture back into the viewing area. And as we head into the weekend, the Gulf moisture looks like it gets a bit of a boost (added lift) from both the north and the south. An upper-air trough will be sliding west-to-east across the central U.S. this week, breaking down the high-pressure ridge that has persisted over the Southern U.S., while northbound energy coming out of the Caribbean heads towards the central Gulf Coast by the weekend. 

In short: a rainmaker’s sandwich.

For Thursday and Friday, we’ll call for morning lows in the BR metro area in the low to mid 70°s, with afternoon highs in the low 90°s. Set afternoon rain chances at about 30% under an afternoon sun/cloud mix for Thursday, then 40% for Friday afternoon and early evening.

At this stage, the Labor Day weekend is shaping up to be a fairly soggy one. Showers and t-storms are likely for Saturday, with rain chances on Sunday at 50% or better. The rain and clouds should keep most at or below 90° over the weekend, but the trade-off could be localized nuisance flooding. (Note: localized .. not widespread)

With a little luck, Monday should be a bit better, but even then we’re carrying scattered afternoon showers and storms in the outlook.

Elsewhere in the tropics, ‘Category 1’ Cristobal is holding strong but is no threat to the U.S mainland nor to Bermuda. While Cristobal will still be on the weather maps this weekend, ‘he’ is headed towards the northeast and will be tracking over cooler Atlantic waters. A weak tropical wave about 400+ miles east of the Lesser Antilles (formerly labeled as “Invest 97L”) offers no serious threat for development, at least not over the next several days. (We will keep an eye on this wave, however, as some of the guidance suggests that it might re-fire over the western Caribbean or southern Gulf. Lastly, the NHC is also watching a healthy tropical wave about to enter the eastern Atlantic from the African continent, but it is simply too far away to worry about.

As for the Saturday night football outlook, whether you are headed to Houston for LSU’s match-up with Wisconsin (8pm kick-off), following the Jags to Lafayette to take on the Ragin’ Cajuns (6pm kick-off) or catching the SLU Lions at home in Hammond (7pm) against Jacksonville, fans will want the raingear handy. We’ve got scattered-to-likely rain chances at all three locations, especially during the afternoon tailgating hours.