New Update on Tropical Storm Ernesto – 10pm Saturday Update

TROPICAL STORM ERNESTO DISCUSSION NUMBER  14
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL052012
1100 PM EDT SAT AUG 04 2012

DESPITE AN IMPRESSIVE APPEARANCE IN INFRARED IMAGERY…MICROWAVE IMAGERY AND REPORTS FROM AN AIR FORCE RESERVE HURRICANE HUNTER AIRCRAFT INDICATE THAT ERNESTO HAS LOST SOME ORGANIZATION DURING THE PAST SEVERAL HOURS.  THE MICROWAVE DATA SUGGESTS THAT THE LOW-LEVEL CENTER HAS BECOME PARTLY EXPOSED TO THE NORTHWEST OF THE STRONG CONVECTION…AND THE AIRCRAFT REPORTS THAT THE CENTRAL PRESSURE HAS RISEN TO 1007 MB.  SINCE THE PLANE HAS NOT YET FULLY SAMPLED THE NORTHEASTERN QUADRANT WHERE THE STRONGEST WINDS WERE FOUND EARLIER…THE INITIAL INTENSITY IS HELD AT 50 KT.  HOWEVER… IT IS POSSIBLE THAT THIS ESTIMATE IS GENEROUS.

THE LOW-LEVEL CENTER HAS ACCELERATED WEST-NORTHWESTWARD SINCE THE LAST ADVISORY…WITH A SHORT-TERM FORWARD SPEED OF OVER 20 KT.  A LONGER-TERM MOTION IS 285/19…WHICH IS THE INITIAL MOTION FOR THE ADVISORY.  THE REASON FOR THIS TRACK CHANGE IS UNCLEAR.  HOWEVER… THE GUIDANCE IS IN GOOD AGREEMENT THAT ERNESTO SHOULD RESUME A WESTWARD MOTION DURING THE NEXT 12 HR OR SO ON THE SOUTH SIDE OF THE SUBTROPICAL RIDGE.  AFTER 24-36 HR…THE RIDGE SHOULD GRADUALLY WEAKEN AS A MID/UPPER-LEVEL TROUGH DEVELOPS OVER THE EASTERN UNITED STATES.  WHILE SOME SPREAD REMAINS…THE GUIDANCE HAS COME INTO BETTER AGREEMENT THAT ERNESTO WILL TURN WEST-NORTHWESTWARD AT A REDUCED FORWARD SPEED AFTER 36 HR…MOVING OVER THE YUCATAN PENINSULA OF MEXICO BETWEEN 72-96 HR AND REACHING THE SOUTHERN OR SOUTHWESTERN GULF OF MEXICO BY THE END OF THE FORECAST PERIOD.  THE NEW FORECAST TRACK IS SHIFTED A LITTLE NORTH OF THE PREVIOUS TRACK THROUGH 24 HR DUE TO THE INITIAL MOTION.  HOWEVER…IT HAS BEEN SHIFTED SOUTHWARD AFTER THAT TIME TO LIE NEAR THE VARIOUS CONSENSUS MODELS.  OVERALL…THE NEW FORECAST TRACK IS FASTER THAN THE PREVIOUS TRACK.

IT IS ALSO UNCLEAR WHY ERNESTO HAS LOST ORGANIZATION SINCE THE OUTFLOW IS GOOD IN ALL DIRECTIONS…THE VERTICAL WIND SHEAR IS LIGHT…AND THE SEA SURFACE TEMPERATURES ARE WARM.  ONE POSSIBLE CAUSE MIGHT BE DRY AIR SEEN IN WATER VAPOR IMAGERY WEST OF THE CYCLONE.  THE DYNAMICAL GUIDANCE CONTINUES TO SUGGEST THAT ERNESTO WILL NOT STRENGTHEN MUCH BEFORE REACHING THE NORTHWESTERN CARIBBEAN…WHILE THE STATISTICAL-DYNAMICAL MODELS CONTINUE TO FORECAST STEADY STRENGTHENING THROUGH THE FORECAST PERIOD.  GIVEN THE TRENDS DURING THE PAST 24 HR…THE NEW INTENSITY FORECAST CALLS FOR A LOWER INTENSIFICATION RATE THAN THE PREVIOUS ADVISORY…WITH ERNESTO BECOMING A HURRICANE IN 48 HR.  GIVE THE DIVERGENT GUIDANCE…THE INTENSITY FORECAST REMAINS OF LOW CONFIDENCE.

Send us your weather pictures! Send them to weather@wvuatv.com. Also, look us up on facebook and twitter. Like us on facebook by searching facebook.com/wvuaweather or WVUA-TV Weather. You can find us on twitter by searching weather@wvuatv.comor WVUA-TV Weather. Great way to get weather updates! Plus, facebook is a great way to send us weather pictures. Simply tag us!

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Richard Scott

WVUA Chief Meteorologist

rscott@wvuatv.com

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Scattered Storms Continue… Saturday Evening Forecast Discussion – 9pm

Good Saturday evening to you! Only a few scattered storms popped up on radar this afternoon and evening; in-fact, I got a strong storm over my house in Northport around 6pm this evening. Most spots around west and southwest Alabama stayed dry due to the lack of a lifting mechanism over our area. We had plenty of moisture and heat for storms, but there was nothing to get the air rising such as a weak disturbance. I was expecting a small scale lifting feature to move into Alabama today, but it stayed just north of us. Numerous showers and storm formed in northwest Alabama and Tennessee earlier today.

With the lack of a lifting feature in here on Sunday, I’ve dropped the rain chances down to 40%. I still expect a good coverage of scattered storms, but they should be a little more hit or miss than previously thought. This is better news if you are going to Fan Day at Bryant-Denny Stadium in Tuscaloosa. You still need the rain gear because the chance of scattered storms will be there through the entire day. The best chance of storms will happen between lunch and 7pm tomorrow evening. A weak cold front is moving our way and will impact our weather on Monday and Tuesday. Look for a good chance of scattered to numerous storms both days, as strong lift moves into our area. A deep layer of tropical moisture and heat over Alabama will serve as fuel to the storms as well, so look for storms to produce heavy rain and intense lightning.

The weak cold front will stall out right over Alabama on Wednesday and Thursday. We can expect the risk of scattered storms to continue each day next week, with rain chances in the 40% range on Wednesday through Friday. It will not rain at your house every day next week, but you’ve got a fair shot of a nice downpour anytime. The best chance of rain will occur between lunch and 9pm on Wednesday through Friday, but a stray morning storm can’t be ruled out. Highs will remain in the lower to middle 90s under a partly cloudy sky.

The beach forecast is looking fair on Sunday through next Wednesday. Expect a mix of sun and clouds, with the risk of scattered storms. It will not rain all day along the Alabama Gulf Coast or Florida Panhandle, but storms are possible. Highs will remain in the lower to middle 90s.

I’ll have an update on Ernesto around 10pm, when the new information comes out. Looking at forecast data, most computer models are in good agreement that Ernesto will impact the Cancun area, then move west northwest into Mexico or Texas next week. All data has done away with the look of a north turn. We’ll watch it close, but confidence is increasing that this system will not impact our local weather.

Send us your weather pictures! Send them to weather@wvuatv.com. Also, look us up on facebook and twitter. Like us on facebook by searching facebook.com/wvuaweather or WVUA-TV Weather. You can find us on twitter by searching weather@wvuatv.comor WVUA-TV Weather. Great way to get weather updates! Plus, facebook is a great way to send us weather pictures. Simply tag us!

Join us live on WVUA-TV weekdays at 4, 5, 6 and 10 pm and weekends at 10pm for the very latest on your news, weather and sports.

Richard Scott

WVUA Chief Meteorologist

rscott@wvuatv.com

Few Scattered Storms Today, Higher Rain Chances Sunday Through Tuesday… Saturday Update 3:20pm

Good Saturday afternoon to you! I’ll admit, we’re drier than I expected we would be at this point. There are big storms on radar across the southeast, but there’s a void of rain in the Tuscaloosa and Birmingham area. You can see the big void of precip over our area, with storms all around us. With more sun today, temperatures have got rather hot, with many spots well into the 90s. Scattered showers and storms should pop up on radar this afternoon and evening across parts of west and central Alabama, but there’s just not much lift to get the storms going today. That being said, keep the rain gear handy today, but the risk of rain is a bit lower for the rest of the day. Temperatures will remain in the 90s this afternoon, then falling into the 80s after sunset.

We should notice an increase in showers and storms on Sunday. Showers and storms are possible at any point on Sunday and Monday. It will not rain all day and not everyone will get rain. There’s even a risk of a few storms tonight, but the chance is looking pretty low. Rain chances will increase to 60% on Sunday. Expect a mix of sun and clouds through Sunday and Monday. Rain chances will remain fairly high through Monday and Tuesday as a cold front moves in from the northwest. The front will help kick off showers and storms in our area at any point Sunday through Tuesday. Again, it won’t be an all day type of rain, but a good downpour is possible at any point.

We’re watching Tropical Storm Ernesto develop this afternoon. At this point, most data takes this system towards Mexico with no impact here. A few models do track it to the north in response to a weak upper air trough. We’ll have to keep a close eye on that incase the path changes. I’ll keep you updated on the forecast trends.

Send us your weather pictures! Send them to weather@wvuatv.com. Also, look us up on facebook and twitter. Like us on facebook by searching facebook.com/wvuaweather or WVUA-TV Weather. You can find us on twitter by searching weather@wvuatv.comor WVUA-TV Weather. Great way to get weather updates! Plus, facebook is a great way to send us weather pictures. Simply tag us!

Join us live on WVUA-TV weekdays at 4, 5, 6 and 10 pm and weekends at 10pm for the very latest on your news, weather and sports.

Richard Scott

WVUA Chief Meteorologist

rscott@wvuatv.com

Tropical Storm Florence Forms in Atlantic – Saturday 2:15 p.m.


TROPICAL STORM FLORENCE ADVISORY NUMBER   3
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL062012
1100 AM AST SAT AUG 04 2012

...FLORENCE A LITTLE STRONGER OVER THE EASTERN ATLANTIC...

SUMMARY OF 1100 AM AST...1500 UTC...INFORMATION
-----------------------------------------------
LOCATION...14.8N 30.6W
ABOUT 415 MI...665 KM W OF THE SOUTHERNMOST CAPE VERDE ISLANDS
MAXIMUM SUSTAINED WINDS...45 MPH...75 KM/H
PRESENT MOVEMENT...WNW OR 295 DEGREES AT 16 MPH...26 KM/H
MINIMUM CENTRAL PRESSURE...1002 MB...29.59 INCHES

WATCHES AND WARNINGS
--------------------
THERE ARE NO COASTAL WATCHES OR WARNINGS IN EFFECT.

DISCUSSION AND 48-HOUR OUTLOOK
------------------------------
AT 1100 AM AST...1500 UTC...THE CENTER OF TROPICAL STORM FLORENCE
WAS LOCATED NEAR LATITUDE 14.8 NORTH...LONGITUDE 30.6 WEST. FLORENCE
IS MOVING TOWARD THE WEST-NORTHWEST NEAR 16 MPH...26 KM/H.  THIS
GENERAL MOTION WITH SOME DECREASE IN FORWARD SPEED IS EXPECTED FOR
THE NEXT COUPLE OF DAYS.

MAXIMUM SUSTAINED WINDS HAVE INCREASED TO NEAR 45 MPH...75
KM/H...WITH HIGHER GUSTS.  NO SIGNIFICANT CHANGE IN INTENSITY IS
EXPECTED DURING THE NEXT COUPLE OF DAYS.

TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 45 MILES...75 KM
FROM THE CENTER.

ESTIMATED MINIMUM CENTRAL PRESSURE IS 1002 MB...29.59 INCHES.

HAZARDS AFFECTING LAND
----------------------
NONE

NEXT ADVISORY
-------------
NEXT COMPLETE ADVISORY...500 PM AST.

Daniel Sparkman
dsparkman@wvuatv.com
WVUA Weather

Thoughts on Ernesto…. Will It Impact Alabama or Mexico? Saturday Morning Update 9am

Good Saturday morning to you! Tropical Storm Ernesto is looking really good this morning in terms of thunderstorm convection and outflow. This is becoming a very healthy system as it moves though the Caribbean this morning. Deep thunderstorms around the center of circulation will allow pressure to continue to fall and windspeed to continue to increase. I wouldn’t be shocked if this is upgraded to a hurricane today or tomorrow, unless something changes. The environment is become more and more conducive for development, so the big question now comes into play… where does he go from here?

Above is the latest 12z forecast models that indicate the possible path Ernesto will take. There’s two main ideas on the map… One, the storm continues west northwest and hits the ridge to the north and cuts a little more west into Mexico. This would be if the ridge of the Gulf is too strong for it to cut north. A hurricane can’t run into a ridge of high pressure. Hurricanes follow the path of least resistance. Say you’re driving down the road in a new car and the road comes to a fork. One path takes you down a nice, smooth, flat road while the other path takes you into a large brick wall. The brick wall is the ridge and the nice flat road is the easiest way around the ridge.

I’m concerned that there will be a weakness between the ridge near the Bahamas and the ridge over Texas. Most forecast data shows a trough moving across the upper midwest, which would form this weakness between the two ridges. I’ve looked back at some past storms and found that storms have turned north into that weakness many times.

Here’s the key… If Ernesto continues to get stronger than expected and becomes a full blown hurricane and if that weakness is there, this storm will move towards the northern or eastern Gulf Coast, as in Louisiana, Mississippi, Alabama or Florida. A stronger storm would more than likely take that path.

If Ernesto is weaker and remains a tropical storm or weak hurricane and the ridge is stronger than expected to the north, the storm will go into Mexico with no issues around here.

It’s going to take another day or two to iron out this, but you notice a few tropical models bring the storm north in 5 to 6 days. We’ve got to watch this! I’m not ready to buy into the storm moving into Mexico just yet. That being said, don’t cancel your beach trip just yet either. Give me another day or two to fine-tune the forecast. If the forecast path changes, I’ll let you know.

Send us your weather pictures! Send them to weather@wvuatv.com. Also, look us up on facebook and twitter. Like us on facebook by searching facebook.com/wvuaweather or WVUA-TV Weather. You can find us on twitter by searching weather@wvuatv.comor WVUA-TV Weather. Great way to get weather updates! Plus, facebook is a great way to send us weather pictures. Simply tag us!

Join us live on WVUA-TV weekdays at 4, 5, 6 and 10 pm and weekends at 10pm for the very latest on your news, weather and sports.

Richard Scott

WVUA Chief Meteorologist

rscott@wvuatv.com

Tropical Storm Erneso Nearning Hurricane Status…Big Questions on Path… Saturday Morning Update 4:25am

TROPICAL STORM ERNESTO DISCUSSION NUMBER  11…CORRECTED
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL052012
500 AM AST SAT AUG 04 2012

CORRECTED TIME OF AMSU PASS IN FIRST PARAGRAPH

THE SATELLITE PRESENTATION OF ERNESTO HAS BEEN GRADUALLY IMPROVING OVERNIGHT. THE COVERAGE OF COLD TOPS HAS INCREASED WHILE CONVECTIVE BANDING FEATURES HAVE BECOME MORE APPARENT AND THE OUTFLOW HAS EXPANDED IN THE NORTHERN SEMICIRCLE. IN ADDITION…AN AMSU PASS FROM 0549 UTC SHOWED A LITTLE BETTER STRUCTURE IN THE INNER CORE. THE INITIAL INTENSITY IS RAISED TO 50 KT BASED ON A BLEND OF THE LATEST DVORAK ESTIMATES FROM TAFB AND SAB.

THE LOW-SHEAR ENVIRONMENT AND IMPROVED STRUCTURE OF THE CYCLONE SUGGEST AT LEAST STEADY INTENSIFICATION OVER THE NEXT COUPLE OF DAYS. HOWEVER…THE DISAGREEMENT IN THE INTENSITY GUIDANCE CONTINUES. THE SHIPS AND LGEM STILL SHOW A FASTER PACE OF INTENSIFICATION…WHILE THE DYNAMICAL MODELS SHOW STRENGTHENING AT A MUCH SLOWER RATE. GIVEN THE CURRENT TRENDS…THE OFFICIAL FORECAST HAS BEEN ADJUSTED UPWARD AND SHOWS ERNESTO BECOMING A HURRICANE IN 36 HOURS…BUT REMAINS BELOW THE STATISTICAL-DYNAMICAL GUIDANCE. LATER IN THE PERIOD…THE GFDL SHOWS MORE INTENSIFICATION THAN EARLIER RUNS…BUT THE HWRF AND MUCH OF THE HFIP GUIDANCE REMAIN WEAKER. AT DAYS 3 THROUGH 5 THE NEW NHC FORECAST HAS BEEN ADJUSTED UPWARD SLIGHTLY…AND IS CLOSE TO THE IV15 CONSENSUS AND THE FLORIDA STATE SUPERENSEMBLE. NEEDLESS TO SAY…THERE IS LOW CONFIDENCE IN THE INTENSITY FORECAST THROUGH THE PERIOD.

THE INITIAL MOTION ESTIMATE IS 275/16 AS ERNESTO IS SITUATED SOUTH OF THE SUBTROPICAL RIDGE. THE TRACK MODEL GUIDANCE IS IN GOOD AGREEMENT THROUGH 48 HOURS IN SHOWING A CONTINUED WESTWARD MOTION AS THE RIDGE BUILDS WESTWARD TO NORTH OF THE CYCLONE. THROUGH THIS TIME THE NHC FORECAST IS SIMPLY AN UPDATE OF THE PREVIOUS ONE. AT DAYS 3 THROUGH 5 THERE CONTINUES TO BE LARGE SPREAD IN THE MODEL GUIDANCE. THE BIGGEST CHANGE THIS CYCLE IS A SOUTHWARD SHIFT IN THE UKMET…WHICH NOW JOINS THE GFS AND ECMWF IN SHOWING THAT ERNESTO WILL REMAIN TOO FAR SOUTH TO MOVE INTO A WEAKNESS IN THE SUBTROPICAL RIDGE THAT DEVELOPS OVER THE EASTERN GULF OF MEXICO IN 4 TO 5 DAYS. HOWEVER…THE GFDL…HWRF…AND SEVERAL OF THE HFIP MODELS CONTINUE TO SHOW ERNESTO GAINING MORE LATITUDE IN THE SECOND HALF OF THE FORECAST PERIOD. THE NHC FORECAST HAS BEEN ADJUSTED A LITTLE TO THE SOUTH TOWARD THE NEW MULTI-MODEL CONSENSUS AT DAYS 3 THROUGH 5…BUT STILL LIES TO THE RIGHT OF THE CENTER OF THE GUIDANCE ENVELOPE.

Send us your weather pictures! Send them to weather@wvuatv.com. Also, look us up on facebook and twitter. Like us on facebook by searching facebook.com/wvuaweather or WVUA-TV Weather. You can find us on twitter by searching weather@wvuatv.comor WVUA-TV Weather. Great way to get weather updates! Plus, facebook is a great way to send us weather pictures. Simply tag us!

Join us live on WVUA-TV weekdays at 4, 5, 6 and 10 pm and weekends at 10pm for the very latest on your news, weather and sports.

Richard Scott

WVUA Chief Meteorologist

rscott@wvuatv.com

Source: National Hurricane Center