Monday, June 30, 2014

Staying Hot & Mainly Dry

By Jay Grymes & Steve Caparotta

WAFB Storm Team QuickCast:

- hot and mostly-dry again for Tuesday
- higher rain chances later in the week
- “Invest 91L” on the verge of becoming the season’s first ‘named’ storm?

It was a summer-season hot and mainly-dry weekend for most WAFB communities and today stayed the course. What’s more, our forecast calls for more of the same for Tuesday and probably Wednesday too.

We closed-out a ‘wet’ June with a final three days of mainly-dry weather across the viewing area. Metro Airport finishes the month with 11.36” of rain, tied with 1962 as the sixth “wettest” June in more than 120 years and the “wettest” June since 2001 (when Allison dumped from 15” to 30” of rain over southeast Louisiana over a 10-day stretch.) 

Mid/upper-level ridging (high pressure) has provided a fairly solid ‘lid’ on the atmosphere, with sinking air suppressing vertical development. We expect that to be the case for at least one more day -- possibly two days -- before the ridge gives way to an advancing upper-air trough and begins to weaken. As it typical for this time of year, even with the upper-air ‘lid,’ spotty showers can’t be ruled out over the next two days. However, those that do get a shower will be the lucky ones: the rest of us will deal with a pair of very hot afternoons, with highs reaching the mid 90°s for parts of the viewing area. Factor in the Gulf humidity and we can expect Heat Index readings in the triple digits for both Tuesday and Wednesday.

Headed into the latter half of the work week -- and into and through the July 4th holiday weekend -- we expect a return to typical summer weather for the region. That means morning lows in the low to mid 70°s, afternoon highs in the low 90°s, and daily rain chances in the 30% to 40% range. The way it looks for now, Friday evening fireworks should go off without a weather-related hitch: any thundershowers that do develop on Friday should be over-and-done before the sky-shows begin (around 9 pm). And for the rest of the holiday weekend? Just more of the same.

In the tropics, eyes are on the area of low pressure off the Florida Atlantic coast and just to the north of the Bahamas labeled Invest 91L. There is clear evidence of a low-level circulation and this afternoon’s visit by a Air Force Reserve Hurricane Hunter found peak winds of 35-40 mph in the vicinity of the center. However, the National Hurricane Center (NHC) failed to upgrade 91L to a tropical cyclone (a depression or tropical storm) because of a lack of widespread thunderstorm activity around the center. Given that 91L as most of the ingredients in place, the NHC is giving 91L an 80% chance of cyclone development in the next two to five days. The good news for us is that the forecast consensus keeps this system out of the Gulf. However, interests along the U.S. Atlantic seaboard should keep close tabs on developments throughout the week.

Sunday, June 29, 2014

Sunday (6/29) Tropical Update

Here is your tropical update for South Louisiana for June 29th, 2014.

All has been quiet this hurricane least for the Atlantic Basin.  But it appears we might be seeing our first tropical system of the season.  An area of low pressure has moved off the coast of Georgia / Florida this weekend.  This broad area of low pressure is not a tropical depression at this time (5:00 PM CDT).  But appears to be getting more and more organized every day.

The National Hurricane Center has classified this disturbance as Invest 91L.  91L is expected to stay in the Western Atlantic slowly drifting South/Southwest.  The NHC is giving this system a 60% chance of becoming a tropical depression in the next 48 hours and an 80% chance over the next 5 days.  Now the good news for South Louisiana is that whatever (if anything) develops is not expected to impact Louisiana or the Gulf of Mexico for that matter.

Model plots continue to indicate a slow drift to the SW before a gradual turn to the North and then Northeast through this week.  This is because the primary steering current will be a trough that will be moving from west to east.  It will block this system from making any westward progress by the middle of the week.  But as it carries it North, the system may clip coastal sections of the Carolinas.

As for intensity...I expect this system to be very slow in getting organized.  Dry air is in the general area and there remains some wind shear in the upper levels.  This should keep this system fairly weak over the next few days.  This is illustrated by our Tropical PrecisionCast.

Tropical PrecisionCast is a high resolution short range model.  It shows a weak area of low pressure sitting off the coast of Florida Tuesday morning.

Image Credit NCAR and can be found at:
About half of the early cycle weather models indicate slow strengthening of this system.  We also don't have complete agreement on tropical storm status being reached.  The GFTI (subset of GFS model) keeps it below Tropical Storm strength.  The GFS or American model which has been the most aggressive tropical formation model so far this system has been very quiet as it pertains to this system showing little if any development.

The European model has been the primary long range global model showing development of this system.  The ECMWF has a possible tropical storm skirting the East Coast July 4th into the holiday weekend.

So here's what you need to know:
1) This system will have NO direct impact and is not headed towards South Louisiana
2) Travel along the East Coast could prove difficult for 4th of July
3) First named storm of the season would be Arthur

10 DAY OUTLOOK: ***(DISCLAIMER: 10 day outlook is a long range forecast and can change rapidly and should NOT be accepted as "gospel" truth but only a small possibility and something to keep an eye on over next several days.)***
The long range models indicate a quiet outlook minus this system previously discussed.  In other words no new systems are expected/indicated.

Tuesday, June 24, 2014

More Rain for Wednesday & Thursday

By Jay Grymes & Steve Caparotta

WAFB Storm Team QuickCast:

- good rain chances for Wednesday & Thursday
- a little “quieter” for Friday & the weekend

A cluster of healthy storms that formed over Acadiana around the lunch hour held together and tracked east-northeast, reaching portions of the WAFB viewing area by the mid-afternoon. Several of the core storms were highly “electrified” and we did see Severe Thunderstorm Warnings posted for a few areas (St. Landry, Avoyelles, Pointe Coupee, West Feliciana, northern Tangipahoa parishes and southern Pike Co.).

And if you happened to get caught beneath one of the stronger afternoon cells you certainly had to deal with a serious downpour or two as well as some vivid lightning. There were even a few reports of wind damage around the area, including 2 minor injuries to infants in Kentwood when a tree fell on a house and some of the falling ceiling material caused some scratches.

Most WAFB neighborhoods can expect a dry but muggy start to Wednesday with mostly cloudy skies and patches of mainly-light early morning fog. Sunrise temps should be in the low to mid 70°s for most WAFB communities. But rains will be more widespread for Wednesday … and Thursday.

The high-pressure ridging that has limited afternoon storm development over the last several days will take a short vacation from our viewing area, allowing for scattered to numerous afternoon and early evening rains for the next two days. We’ll post rain chances at 60% to 70% -- which means that most neighborhoods will get at least a little rain. These won’t be all-day rains, just a broader coverage each day. The better rain chances also mean that most or all of us top-out in the 80°s for the next two afternoons.

As we head into Friday and the weekend, the guidance indicates that the high will sneak back into the weather mix, once again limiting -- but not shutting-off -- the opportunity for afternoon rains. We’ll go with a 30% rain chance for Friday, Saturday and Sunday -- back to something more typical for late June. That also means that the 90°s will return for the weekend as well.

It’s Lightning Awareness Week, and we note that Louisiana ranks among the deadliest states for lightning when weighted by population size. There have been 17 lightning-related fatalities in the Bayou State since 2000 (14+ years), just over one-per-year, on average. All of the victims were males, most were adults (age 21 or older), all were outside at the time of the accident … and in many cases, witnesses say that it was not raining when the deadly strike occurred.

Lightning safety is simple: when you see a flash or hear a rumble, go inside! Inside can also be a car, a bus … anything enclosed (with the windows up if it’s a vehicle).

All is still quiet in the tropics, with the NHC calling for no development through the next five days, at least.

Monday, June 23, 2014

No Big Changes in the Outlook

By Jay Grymes & Steve Caparotta

WAFB Storm Team QuickCast:

- hot, humid, summertime weather pattern through the week
- slightly higher rain chances around mid-week

We started the day with a band of mostly light-to-moderate rainshowers to the north and west of the Capital City as well as a thundershowers along the coast. But for most WAFB commuters, it was a dry morning drive under mostly cloudy skies. In addition, much of the early-morning rains dissipated into the mid-to-late morning hours. At the same time, the lingering clouds kept temperatures from climbing into the 90°s for many communities and the day’s slower warm-up meant fewer showers and storms for the afternoon.

For the trivia buffs, today is the first day since June 15th with a high under 90° at Metro Airport (BTR).

However, a few showers and storms still managed to pop-up during the afternoon and a few of those storms were rather active in terms of lightning. At this time of year, if the air temps get up into the upper 80°s to near 90°, that is usually enough to fire-up at least a few storms even on a mostly-cloudy day. And as is usually the case, we look for most or all of the day’s rains to dissipate around sunset or soon after.

Frankly, there is nothing new ‘weatherwise’ in terms of our outlook through the coming week. Our daily forecast stays fairly steady right through the weekend:
- sunrise temperatures in the low to mid 70°s with some pockets of mainly-light fog possible,
- afternoon highs in the low 90°s for most WAFB communities, with Heat Index readings
peaking in the mid to upper 90°s, and
- isolated to scattered afternoon thundershowers each day (from 20% to 50% coverage).

Rain chances may shift a little from day to day, but we’re not expecting any all-day rains this week. For Wednesday, we may nudge rain chances up to 50% or so, but the bottom line is a forecast that essentially reads, “More of the same.” But then, that’s how summer rolls in our neck of the woods.

All remains quiet in the tropical Atlantic … and there are no complaints in that department!

This is National Lightning Safety Awareness Week. Lightning is one of the most underrated weather threats, accounting for roughly 50 fatalities in the U.S. each year. For the Bayou State, there have been 17 lightning-related fatalities since 2000 and every one of them occurred to someone outdoors. Louisiana is certainly a hot spot for lightning strikes, ranking as the #2 state for hits (behind Florida). In fact, the number of cloud-to-ground strikes might surprise you: the statewide average is 20 strikes per square mile per year, but the annual average is actually a little higher for the southeastern portion of the state, including the WAFB viewing area! 

Saturday, June 21, 2014

WAFB Storm Team QuickCast:
- summer “officially” began this morning
- not much change in the forecast for the next couple of days
- better rain chances later in the work week

Did you notice the change in seasons this morning when summer kicked-in at 5:51am?  Nope, me neither … but today is the Summer Solstice.  That means for everyone living north of the latitudinal line known as the Tropic of Cancer (23.5°N), two things happen today: (1) the duration of sunlight is the longest of any day in the year and (2) the mid-day sun reaches its highest point in the sky of any day in the year.

For Baton Rouge, today’s “sunrise-to-sunset period” is roughly 14 hours and 7 minutes.  Starting tomorrow, that length of time will slowly decline, and will continue to do so until the Winter Solstice (on December 21st).  The other bit of trivia is that at about 1:06pm, the sun was almost directly overhead for Baton Rouge (that will be the case tomorrow as well).  Directly overhead would mean a solar altitude of 90° ... today’s solar peak altitude for the Red Stick was roughly 83° (also occurring at about 1:06pm).

As for the metro area weather over the coming days … no notable changes, at least in the short term.  Rain chances will run around 30% for Sunday, but that’s not much of a change from what we’ve seen the last several days.  And after another morning start for the Capital City in the low 70°s, we’ll return to the low 90°s for Sunday afternoon under a sun/cloud mix.  Yes, a few neighborhoods will deal with a thundershower, but the afternoon heat will be the bigger weather story for most WAFB communities, with the peak mid-afternoon Heat index once again returning to the mid-to-upper 90°s.

The forecast looks about the same for Monday too, as well as Tuesday.  But we are going to ‘up’ those percentages a bit as we head into the middle and latter part of the work week. The upper-air ridging that has helped minimize afternoon shower development over the better part of the past week will no longer be a significant factor in our regional weather.  As a result, by taking the ridge’s “lid” off the atmosphere, daytime heating will help lift our moist, unstable air mass; that should lead to more widespread afternoon action and better rain chances.

In the tropics, the National Hurricane Center is watching an area in the western Atlantic roughly 200 miles east of the Georgia/Florida coast.  This area has a very low probability for development over the next few days.  In addition, even if it were to get better organized in the coming days, all indications are that it would move towards the northeast -- away from the U.S. coastline.  Elsewhere, all appears quiet in the Gulf, the Caribbean and the remainder of the tropical Atlantic.

Thursday, June 19, 2014

Hot, Iso'd T-Storms...You Know the Drill

By Jay Grymes & Steve Caparotta

WAFB Storm Team QuickCast:

- plan on more of the same summer “sultries” right through Sunday
- summer officially begins on Saturday morning (at 5:51am CDT)
- hit-n-miss afternoon thundershowers for Friday & the weekend

Our high today at Metro Airport of 93° is the highest reading of the year thus far. But we are almost certain to top that in the coming weeks.

We’ll keep this short since the forecast reads the same as it has for most of the week. To summarize, the outlook for Friday and the weekend looks like this:
- morning lows in the low 70°s for most of us with patchy, mainly-light fog near sunrise,
- afternoon highs running in the low 90°s with peak Heat Index readings in the mid to upper 90°s, and
- afternoon rain chances running around 20% to 30% each day.

The upper-level ridge that has kept a modest ‘lid’ on our afternoon t-shower development remains in play, but it continues to slowly weaken. We still think that it will continue to hamper the onset of afternoon rains but may ‘soften-up’ just enough to allow a very slight increase in rain coverage over the weekend. So let’s call it a 20% rain chance for Friday and Saturday and then at about 30% for Sunday -- which means most WAFB neighborhoods remain dry each day.

Here’s a little ‘math’ game if you are into raw statistics. If we assume that chances-of-rain for your yard are 20% for both Friday and Saturday and then 30% for Sunday, what are the chances that you go all three days without any measurable rain? If you’ve never contemplated this one, the purely ‘mathematical’ solution is not as simple as you might first think.

The answer is: [(1 - 0.2) x (1 - 0.2) x (1 - 0.3)] = [(0.8) x (0.8) x (0.7)] = 0.448

. . . roughly a 45% chance (44.8%) that you go through Friday, Saturday and Sunday without getting any rain at all. In other words, even with our relatively low day-to-day rain percentages, there is better than a 50-50 chance you’ll get at least one sprinkle sometime over the next three days. And even with those low percentages, a few of you will see rain on two or more days.

And remember that the “chance of rain” does not translate into a forecast for an “amount of rain.” Just like we’ve seen the past several days, although the majority of WAFB neighborhoods have remained dry each afternoon, a someone has gotten something each afternoon. And one or two of those neighborhoods have experienced significant downpours. The truth is, forecasting exactly where it will rain in the summer is almost impossible ... and how much it will rain at any one place is just as difficult!

Here’s some good news: it remains quiet in the tropics and is expected to stay that way through the next several days, at least.

Tuesday, June 17, 2014

- no significant changes to the forecast through the next five days, at least
- hot & humid afternoons continue into the weekend
- staying with 20% to 30% rain chances each day
Not much to talk about really: “What you see is what you get.” Looks like we are locked into a daily pattern of humid Gulf air, daytime heat, and afternoon ‘hit-or-miss’ thundershowers. The forecast numbers for the rest of the week are just about ‘normal’ for June and there’s nothing in the short-term forecast that appears ready to change it up.
So here it is -- and it’s not really any different from yesterday: morning lows in the low 70°s for most of us (mid to upper 70°s closer to the coast), afternoon highs running around 90° to 92° (upper 80°s along the coast), and afternoon rain chances running around 20% to 30% -- each day. Factor in the heat and humidity and you can expect Heat Index readings at or above 90° for several hours with peak afternoon Heat Index numbers in the mid to upper 90°s. And don’t forget, the Heat Index is the ‘feels like’ temperature in the shade -- direct sunshine can add another 10° or more to the ‘apparent’ temperature.
(By the way, if you are thinking that this you read virtually the same thing yesterday, you’re right!)
The near-steady inflow of Gulf air will keep dew points near or above 70° through the week. That comes with a daily early-morning forecast for patchy, mainly-light ground fog. Fair to partly-cloudy skies during the first half of the day will become partly-cloudy to a sun/cloud mix by the mid-afternoon for most WAFB neighborhoods as daytime heating works the moist and unstable Gulf air to generate an abundance of cumulus clouds. Some of those clouds will grow into rainmakers.
The upper-level ridge that I showed you on Monday afternoon an evening persists over the southeastern U.S. and the current guidance keeps it there through Friday, at least. That upper-air dome will continue to limit the onset of widespread afternoon rains through the remainder of the work week but will not fully stop the development of a few healthy thundershowers each day. The moist-and-unstable Gulf air is getting a lifting boost from the daytime heating, and a few of those vertically-developing clouds will pop-through the ‘capping’ effect of the upper-level ridge.
Result: a 20% to 30% coverage of mainly-afternoon rains with a few lightning strikes mixed- in for a few WAFB communities. And just like the past couple of days, whatever rains do develop wind down near sunset each day.
All looks good (quiet) in the tropics for the time being. A couple of tropical waves are evident on satellite imagery, but there is far too much shear on-going over the basin for any waves to show an organizing trend for now. That’s not uncommon this early in the Hurricane Season. The bigger question is, “Will an El Niño develop later this summer and help to maintain a hostile, shearing environment?”

Monday, June 16, 2014

Feeling Like Summer . . .

WAFB Storm Team QuickCast:
- hot, humid, summertime weather pattern through the week
- 20% to 30% rain chances each day
Summer may not ‘officially’ begin until Saturday (June 21st at 5:51am CDT) but this week will certainly have a summer-like feel to it weatherwise. The WAFB Storm Team forecast through the coming week remains essentially unchanged each day: morning lows in the low 70°s for most of us (mid to upper 70°s closer to the coast), afternoon highs in the 90°s (upper 80°s along the coast), and afternoon rain chances running around 20% -- to maybe 30% -- each day.
The ‘muggies’ will stay with us through the week and into the weekend with dew point readings generally near or above 70°. Morning commuters can expect patchy, mainly-light ground fog in the usual spots. For the afternoons, the combination of heat and humidity will push peak Heat Index readings up in the mid-to-upper 90°s range for many of us. And just like we’ve seen over the past few days, the majority of WAFB neighborhoods will stay dry each day (with our mainly-isolated afternoon thundershowers) but those that do get a storm overhead could be dealing with a serious downpour as rainshowers may be slow to move wherever they develop.
We are not expecting any frontal passages through the week, which means warm-and-moist Gulf air will remain in place with no relief from the afternoon heat and humidity unless you happen to be under one of the afternoon rainshowers and storms.
An upper-level ridge will remain over the southeastern U.S. while surface high pressure noses under that upper-air dome from the east into the eastern Gulf (the Bermuda High). While the upper-ridge will serve as an inhibitor to the onset of widespread rains this week, the surface pattern will maintain a southeast-to-southerly low-level flow off the Gulf. Given the daytime sunshine and steady inflow of Gulf humidity, we can expect to see ‘hit-or-miss’ (20% to 30% coverage)‘sea-breeze’ showers rolling from south-to-north through the viewing area each afternoon. Most or all of the action should end near or soon after sunset each day.
We started today with a few modest showers along the coast -- we can expect similar starts to the coming days. Under this kind of weather regime, we will often observe inland showers during the afternoon and pockets of showers over the coastal waters developing in the late night and pre-dawn hours. Some of those coast showers can slip northward into the coastal parishes early in the morning but usually dissipate by mid-morning.
And in the tropics … all remains quiet for the Atlantic Basin.

Sunday, June 15, 2014

Sunday (06/15) Tropical Update

Here is your tropical update for South Louisiana for June 15th, 2014.

The start to the Atlantic hurricane season 2014 has been a fairly quiet one.

The Pacific Basin is already through its third named storm after major hurricane Christina formed in the Eastern Pacific.

You'll notice some cloud cover over towards Central America.  That is a very broad trough and is expected to move inland over the next day or so.  So nothing to worry about there.  The National Hurricane Center in Miami, FL is continuing to give the all clear for not only the next 2 days but also the next 5 days.  No tropical cyclone formation is even hinted at on short and medium range models.

Typically in June we keep our eyes on 3 distinct areas for possible tropical formation.

1) The Gulf of Mexico
2) The Western Caribbean
3) The SW Atlantic / Bahamas

10 DAY OUTLOOK: ***(DISCLAIMER: 10 day outlook is a long range forecast and can change rapidly and should NOT be accepted as "gospel" truth but only a small possibility and something to keep an eye on over next several days.)***
If you remember last week we mentioned a possible spin up of a tropical system according to the GFS (American) model.  The GFS was out on a limb as it was the only long range model indicating any development within the 10-14 day outlook.  The GFS placed a system in the Gulf of Mexico during the middle of what has become this week.

GFS Model for Thursday June 19th @ 6:00 PM
The latest, and past several, GFS model runs have backed off completely of developing anything remotely tropical over the next 14 days (the length of the model).  As you see in the image above the GFS has only normal shower activity in and around the Gulf of Mexico by mid week.

None of our other weather models are indicating any kind of development either.  So we appear to be in the clear for the next two weeks at this time.

Friday, June 13, 2014

Less Rainfall into the Weekend

By Jay Grymes & Steve Caparotta

WAFB Storm Team QuickCast:
- clearing continues this evening
- hot & mostly-dry for Saturday
- hot & humid, isolated afternoon t-showers for Father’s Day

It sure was a messy first half of the day, with thunderstorms, gusting winds, small hail and locally heavy downpours around much of the WAFB viewing area. The stormy weather was courtesy of a squall line/outflow boundary generated by a southeast bound disturbance that moved through the region. By the afternoon, the weather was settling down for most WAFB neighborhoods, but only after rains of up to 1” to 2” in places, minor wind damage in spots, and reports of power outages.

While the big rains are over, a few neighborhoods could still get a sprinkle during the late afternoon and early evening hours as a weak, quasi-stationary front lingers over the lower Mississippi Valley. But for most of us, this should be a fairly nice Friday evening.

Skies should become fair overnight with a mild sunrise for Saturday morning with lows in the upper 60°s to low 70°s across the viewing area. We’ll go with partly cloudy skies for Saturday afternoon and highs in the low 90°s for the BR metro area. We can’t rule out a spotty shower on Saturday afternoon, but the vast majority of us will stay dry.

For Father’s Day, we’ll bring in a 20% to 30% rain chance - - mainly the afternoon variety - - with otherwise partly cloudy skies and highs again up around 90° or so. All in all, Sunday should cooperate for all of the fathers, with a decent morning for the golf game and just a scattering of mainly short-lived showers in the afternoon for the grilling time. 

Our forecast for next week reads like a “copy & paste” repeater: morning lows in the low 70°s and afternoon highs in the low 90°s under partly cloudy skies with isolated afternoon showers.

Nothing to talk about in the tropics … so enjoy the hot weekend … 
and Happy Father’s Day to all the Dads, Granddads and Great Granddads!

Sunday, June 8, 2014

Sunday (06/08) Tropical Update

Here is your tropical update for South Louisiana for June 6th, 2014.

After watching the first invest of the season (90L) dissipate in the Bay of Campeche, the National Hurricane Center has given the all clear for the Atlantic Basin for the next 5 days.

The Pacific Basin though has one area of low pressure that is currently being monitored.

A 50% probability has been given for an area of low pressure moving NW just off the coast of Mexico.  This could become the Pacific Basin's next tropical depression in the next day or two.  It poses no threat to South Louisiana.

10 DAY OUTLOOK: ***(DISCLAIMER: 10 day outlook is a long range forecast and can change rapidly and should NOT be accepted as "gospel" truth but only a small possibility and something to keep an eye on over next several days.)***
As we look beyond the 5 day window, one of our more reliable long range models is picking up on something.  The GFS (American) model is picking up on an area of low pressure developing in the Western Caribbean near the Yucatan Peninsula 7 days out Sunday June 15th.

GFS Model: Sunday June 15th @ 4 PM

The GFS model then takes this low north and slowly develops it as it moves into the Gulf of Mexico.

GFS Model: Wednesday June 18th @ 6 AM

The image above from Wednesday morning June 18th shows a tropical depression or weak tropical storm sitting in the North Central Gulf of Mexico.

On the flip side here is an image taken from the same exact time from one of our other reliable models the ECMWF (European) model.

ECMWF Model: Wednesday June 18th @ 6 AM
As it pertains to model accuracy early this season so far; the GFS did indicate the formation of Invest 90L several days before the ECMWF.  But, the GFS didn't do well was predict the path and development of 90L.  The ECMWF did show 90L a couple of days out before forming.  It was the best performing model as it pertains to the actual path and development on the low pressure system.

So what should we take away from this?

1)  There is by no means a guarantee we will be dealing with a tropical system of some kind 10 days from now.
2)  This is something we will be watching for over the next several days. (still 7 days from even forming!)
3)  Stay with WAFB Weather, we'll keep you updated...

Thursday, June 5, 2014

Summertime Feel thru the Weekend!

- stays mainly-dry thru the weekend
- 30% chance for development in the SW Gulf
The morning began with sun-up temperatures in the low 70°s for the Red Stick with patchy, mainly-light fog around the WAFB viewing area. You can expect more of the same each morning right through the weekend and into next week. In fact, some of you may only see lows dip to the mid 70°s by the weekend, a reflection of increasing low-level Gulf moisture and a signal that the air will become even more ‘sticky’ in the coming days.
As for highs .. a good portion of the viewing area finally reached the 90°mark this afternoon. For Baton Rouge, the all-time latest “first 90°-day” ever is June 10th, set in 1976 & 1950. It looks like we’ll try and make up for this year’s lack of 90°s quickly, with highs of 90° or above on the forecast board for the next three days, at least. 
An upper-level ridge centered over central and southern Texas and extending into northern Mexico is readily visible on the water vapor satellite imagery. Although “flattening” a bit in the coming days (not extending all that far to the north), the upper ridge is expanding eastward. Dry, sinking air associated with the upper ridge will inhibit the opportunity for our moist, warm and unstable Gulf air to rise -- that means reduced cloud cover and little chance of rain until the ridge breaks down. As of this afternoon, guidance suggests that the ridge will remain in play into the weekend and probably all the way through the weekend. That translates into “hot, humid but mainly-dry” down here on the ground.
We can’t completely rule out a rogue shower over the course of the next three days -- just like the one that bubbled-up over WBR Parish and drifted north last evening. But even if a brief shower does pop-up on Titan9 Doppler over the next few days, it won’t last long and won’t amount to much. Let’s set rain chances at 10% or less for Friday and Saturday and less than 20% for Sunday.
It’ll be a “sunscreen weekend” across the viewing area.
The ridge will start to weaken/breakdown late Sunday or Monday, allowing for the unstable Gulf air and the summer heat to start doing their “thing” by the early-to-middle part of the upcoming work week. We’ll call for isolated afternoon showers on Monday with scattered afternoon thundershowers for Tuesday, Wednesday and probably Thursday too. We also may take a break from the 90°s thanks to the increasing cloud cover and associated rain chances next week.
And about the disturbance in the SW Gulf: as we’ve been saying each day, this is certainly nothing to get worked-up about, at least not for the time being. The disturbance remains unorganized and the National Hurricane Center (NHC) has development potential at a low 30% for the next two to five days. In other words, the way things look right now, this is of no concern through the weekend and well into next week.  In fact, the NHC canceled the planned flight into the storm today, indicating that they have little worry about this quickly spinning-up into something serious.  However, even if it remains rather disorganized through the next several days, it has already benn producing flooding rains for parts of Mexico.
 We know that many of you are already looking at the forecast model tracks -- things like the on-line “spaghetti plots.” You can find them all over the web these days. And yes, we look at them too (along with other forecast tools).
But keep this in mind: these forecast models require a storm center, a central low, to “initialize” (to start) their forecast runs. Yet we don’t have a low-pressure center in the SW Gulf, so these model runs are based on a “best-guess/what-if” location of a potential center. Making a forecast decision based on tropical forecast models that were run without a defined center of circulation is getting awfully close to calling a pitch a strike before the pitcher has even let go of the ball.
So let’s all relax and enjoy the weekend: we’ve got six months of potential tropical action ahead. If -- IF! -- something does develop in the Bay of Campeche, we’ll let you know during our weathercasts and through social media.
In the meantime, be careful in the summer-like heat.

Wednesday, June 4, 2014

Getting Hot, Staying Dry ... and the SW Gulf

- hot, humid but mainly-dry for the rest of the week
- not a threat but worth a watch in the southwestern Gulf

While you might not call it uncomfortable, overnight readings hung in the 70°s for many WAFB neighborhoods and that will continue through the week. Muggy -- yet not oppressive -- with enough moisture in the air to reach saturation (relative humidity of 100%) near sun-up and that means patchy fog. Count on more of the same through the week.

As for today, morning and mid-day clouds generated some spotty, brief showers around south Louisiana. But maybe more importantly, they slowed the daytime warm-up, which meant that Baton Rouge’s Metro Airport still didn’t quite make the ‘magic’ 90° mark today.

Can we dodge the 90°s again tomorrow? Doubt it. The upper-level ridge over Texas should expand far enough to the east by tomorrow to cut down on the daytime clouds, not only keeping us even drier than today but also allowing a faster warm-up due to more sunshine. We’ll call for a high on Thursday right around 90° with highs for Friday through Sunday also at or just above 90°. Morning starts for all four days will be in the low 70°s for metro BR.

The ridge will start to breakdown over the weekend. We’ll go with spotty afternoon showers for Saturday (less than a 20% chance) and isolated afternoon and early evening showers (20% rain chance) for Sunday. In essence, the weekend stays mostly dry – enjoy, but remember the sunscreen and careful in the June heat!

We’ll ease the rain chances up early next week: 30% rain chance for Monday and scattered mainly-afternoon rains for Tuesday and Wednesday.

And what about that ‘thing’in the southwestern Gulf? First off, let’s not get excited just yet.

Development, if it does occur at all, looks like it will be very slow. There remains plenty of mid/upper-level shear over the Gulf. And while SSTs (sea-surface temperatures) in the southern Gulf are warm enough to support a storm, the warm waters don’t extend to a great depth. Since the disturbed weather doesn’t appear ready to move away from the Bay of Campeche anytime soon, just sitting there will turn-over and stir the deeper waters enough to potentially cool the surface.

On the other hand, remnants of BORIS (the landfalling tropical depression from the eastern Pacific) could give the broad area of low pressure a little energy nudge in the next few days.

So what to make of it? It’s early in the season. Frankly, if it weren’t in the Gulf, I’d be giving it a “never mind.” But anything in the Gulf deserves at least a little attention -- and the WAFB Storm Team has you covered.

Now is a good time to review your preparedness plans. Think about it: would you be ready if that blob in the SW Gulf ramped up, earned a ‘name,’ and was here by Sunday or Monday?

Monday, June 2, 2014

Trending Drier & Hotter

By Jay Grymes & Steve Caparotta

WAFB Storm Team QuickCast:

- scattered PM rains on Tuesday
- getting drier as the week progresses
- looks like 90°s finally arrive later this week
** A reminder that the WAFB Storm Team’s hurricane special, “The 5th Season” airs tonight, right after the 6:00pm newscast.  We’ll be looking at a variety of topics including: El Niño, ‘Pet Preparedness’ during a storm, the Business Emergency Operations Center at LSU, and recent storm-surge forecast improvements. **
Also, for fans of the night sky, we’ll get a 6-minute look at the International Space Station (ISS) this evening if the clouds cooperate.  Viewing will begin along the southwestern horizon at 9:37pm (your phone likely has a compass tool) with the ISS climbing more than halfway overhead as it heads towards the northeastern horizon.
As for our weather, we watched as a steady fetch from the southeast brought scattered showers and t-storms into the viewing area today.  Most of the rains came during the afternoon but there were a few showers evident on Titan9 Doppler early this morning.  Thankfully, rain totals today were generally under one-half-inch for most WAFB neighborhoods.
Along the area rivers, the Amite showed a second peak at Denham Springs today (as expected), with a minor “wave crest” expected in Port Vincent and French Settlement tomorrow.  The lower Amite can expect water levels to remain close to where they are today through mid-week.  As for the Tickfaw, Holden is showing a steady fall although water levels are likely to remain fairly steady for the next couple of days at Killian.  The Tangipahoa at Robert is falling but remains “in flood” -- that site should drop below flood stage tomorrow morning or mid-day.
Our forecast shows considerable improvement for those looking for a dry spell.  Although we’ll carry a 30% to 40% rain chance in the local forecast for Tuesday, our outlook calls for mainly-dry days from Wednesday through Friday.  At this stage we also expect Saturday to remain dry but will toss-in a 20% chance for afternoon showers on Sunday.
Southeasterly winds through the week will deliver a steady feed of warm-and-moist Gulf air.  Plan on muggy mornings this week with sunrise temperatures in the upper 60°s to low 70°s and patchy morning fog in the usual suspect spots.  Once we get past the modest rain chances on Tuesday, the “drier” pattern we’re expecting this week should mean highs climbing into the low 90°s by mid-week.
By the way, we’re into June and have yet to see a 90° day at Metro Airport.  That’s rather unusual: in fact, this marks only the ninth time since 1930 when the first 90°-day of the year occurred after May 31st.  You’ve got to go back to June 7, 1994 for the last year that the first 90° held off until June.
As a reminder, we’re now into the Hurricane Season: are you ready?  Remember how you fared during Gustav or Isaac?  What more could you have done to better prepare yourself, your family, and your interests?  Check out WAFB’s Hurricane Center at for helpful hints and preparedness guidance!  And “Get a Game Plan.”