Thursday Afternoon Weather Update – 2:45 PM

This afternoon has turned out hot, as temperatures have warmed into the lower 90s. Heat index values are still not bad due to low moisture content. Our dewpoints have stayed in the lower 60s, so the humidity hasn’t been that bad. Typically this time of the year, dewpoints hang out in the middle 70s. The dry air is in response to a cold front that made it through over the weekend. Continental air has taken over much of the eastern US, which gives us a nice break from the heat and humidity. With dry air in place, temperatures at night have been allowed to cool off a good bit. Dry air heats and cools more effectively than moist air. We can expect lows in the upper 60s through the weekend. Highs will remain close to average, with a high between 90 and 93 each day.

Conditions will continue rather settled this evening and on Friday, but some questions come into play on Sunday and Monday. Some data is suggesting a disturbance lifts in out of the Gulf of Mexico. Depending on the amount of moisture return and placement of the disturbance will determine what happens in west Alabama. Data is shifting back into the dry look in west and central Alabama, as high pressure builds in from the east. The best bet of rain will occur along the coast, and over Mississippi. We’ve put a 10 to 20% chance of rain in the forecast on Saturday, Sunday and Monday for now, but we may have to adjust some numbers as the time approaches.

The tropics are very active, as we have Hurricane Danielle and Tropical Storm Earl. Also, another disturbance could become a tropical storm over the next day or so as it progresses westward. This system is well out in the eastern Atlantic, so we’ve got plenty of time to watch that feature. Be sure to join us on WVUA-TV today at 4, 5, 6 and 10 for more on your local weather, news and sports. Have a great day!

Richard Scott
WVUA Meteorologist

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Thursday Morning Weather Update – 9:45 AM

Good Thursday morning! We made it into the 60s again lastnight, which felt very nice. Skies have started out this morning sunny, and our humidity continues to be low. In-fact, conditions feel a bit like fall. Temperature will warm into the lower 90s this afternoon, but it won’t feel as bad due to the lower humidity.

Our local weather will continue to be rather settled over the next few days, as we continue to experience low humidity and comfortable nights. As we move into the weekend, conditions get to be a little tricky. A disturbance lifts northward out of the gulf, and could spread a few showers and extra clouds in here. This will mainly be on Sunday and Monday. Data is going two different ways on this though. I’m leaning more in the direction of additional showers and storms on Sunday and Monday. This would make a big change in the forecast, as we’ll be increasing our rain chances. Due to the addition of clouds and rain, we can expect cooler temperatures; in-fact, some of our data keeps temperatures in the middle 80s on Sunday and Monday.

The tropics have come to life, but any action is staying well away from Alabama. A trough over the western Atlantic is turning all systems northward before reaching the east coast. We’ll have to keep an eye on the Gulf of Mexico, as this is a favorable setup to get some tropical activity into the southeast. Some data was hinting at that yesterday, but this morning’s models are fading away from that idea. If anything tries to fire up, we’ll quickly let you know about it.

Meteorologist Jon Mason will have a fresh discussion this afternoon. Also, join us on WVUA-TV today at 4, 5, 6 and 10 for more on your local news, weather and sports.

Richard Scott
WVUA Meteorologist

Here’s Earl – 9am Thursday

CONVENTIONAL SATELLITE IMAGERY INDICATES THAT THE SPIRAL BANDS AROUND EARL HAVE BECOME BETTER ORGANIZED THIS MORNING… PARTICULARLY OVER THE WESTERN PORTION OF THE CYCLONE. THE CYCLONE STRUCTURE…HOWEVER…IS STILL A BIT ELONGATED ALONG A SOUTHWEST TO NORTHEAST AXIS. DVORAK SATELLITE CURRENT INTENSITY ESTIMATES FROM TAFB AND SAB ARE 45 AND 35 KT..RESPECTIVELY.  USING A BLEND OF THE TWO…THE INITIAL INTENSITY IS INCREASED TO 40 KT. THE OCEAN IS WARM AND THE SHEAR IS LOW…CREATING AN ENVIRONMENT CONDUCIVE FOR STRENGTHENING DURING THE ENTIRE FORECAST PERIOD. IN FACT…THE LGEM…HWRF…AND SHIPS MODELS ALL SHOW THE CYCLONE BECOMING A HURRICANE IN 2 DAYS. THE OFFICIAL FORECAST FOLLOWS SUIT AND ALSO BRINGS EARL TO CATEGORY TWO INTENSITY BY DAY 5.

THE CENTER OF EARL HAS BEEN RATHER DIFFICULT TO LOCATE THIS MORNING. A 2315 UTC ASCAT OVERPASS INDICATED AN ELONGATED CENTER NEAR THE CONVECTION OVER THE SOUTHERN PORTION OF THE SYSTEM…WELL TO THE SOUTH OF THE PREVIOUS ADVISORY POSITION.  HOWEVER…A SUBSEQUENT AMSU-B MICROWAVE PASS AT 2318 UTC AND A RECENT 0430 UTC TRMM IMAGE SUGGESTED THE CENTER IS LOCATED TO THE NORTHEAST OF THE AFOREMENTIONED ASCAT PASS…MUCH CLOSER TO THE PREVIOUS BEST TRACK.  FOR THIS ADVISORY…AND BASED ON THESE DATA…CONTINUITY WILL BE MAINTAINED AND THE INITIAL POSITION IS BE NEAR THE NORTHERN CLUSTER OF DEEP CONVECTION AND CLOSE TO THE TRMM FIX.  IF THE CIRCULATION CENTER DOES REFORM FARTHER SOUTH…THE FORECAST TRACK WILL HAVE TO BE ADJUSTED SOUTH…OR TO THE LEFT OF THIS ADVISORY PACKAGE.

EARL IS MOVING TOWARD THE WEST-NORTHWEST…AN ESTIMATED 285 DEGREES AT 13 KT. THE TROPICAL STORM IS EMBEDDED WITHIN THE DEEP TROPICAL ATLANTIC TRADE WIND FLOW AND SHOULD CONTINUE ON THIS GENERAL TRACK OVER THE NEXT 48 TO 72 HOURS. AFTERWARD…A TURN TOWARD THE WEST-NORTHWEST IS EXPECTED AS THE CYCLONE BEGINS TO MOVE TOWARD A BREAK IN THE SUBTROPICAL RIDGE. WITH THE EXCEPTION OF NOGAPS AND THE NAVY GFDN…WHICH ARE BOTH INDICATING AN EARLIER TURN TOWARD THE NORTHWEST…THE DYNAMICAL MODELS ARE TIGHTLY CLUSTERED THROUGH DAY 5. THE NHC FORECAST TRACK IS BASED ON THE TVCN MODEL CONSENSUS AND IS CLOSE TO THE ECMWF AND GFS.

WVUA Meteorologist Richard Scott

Good Morning Danielle – 9 AM Thursday

 

AN EYE HAS BECOME APPARENT ON INFRARED SATELLITE IMAGERY OVER THE PAST FEW HOURS…ALTHOUGH THE COLDEST CONVECTIVE TOPS AROUND THE EYE HAVE BEEN FLUCTUATING IN COVERAGE.  BASED ON A DVORAK ESTIMATE OF 5.0 FROM TAFB…THE INITIAL INTENSITY IS RAISED TO 90 KT FOR THIS
ADVISORY. UPPER-LEVEL OUTFLOW APPEARS EXCELLENT EXCEPT TO THE SOUTHWEST…AS THE HURRICANE IS CURRENTLY EXPERIENCING SOUTHWESTERLY SHEAR OF AROUND 10 KT ACCORDING TO ANALYSES FROM
UW-CIMSS AND THE SHIPS MODEL.  THE SHEAR IS EXPECTED TO REMAIN LOW FOR THE NEXT 2 TO 3 DAYS…AND THIS SHOULD ALLOW DANIELLE TO INTENSIFY TO MAJOR HURRICANE STATUS IN THE NEXT DAY OR SO.  AFTER 72 HOURS…INCREASING SHEAR DUE TO INTERACTION WITH A MID-LATITUDE TROUGH ALONG WITH COOLER WATERS SHOULD RESULT IN WEAKENING.  THE INTENSITY FORECAST HAS BEEN NUDGED UPWARD AND IS NOW A LITTLE HIGHER THAN THE SHIPS AND LGEM THROUGH 24 HOURS AND IS CLOSE TO THOSE MODELS BEYOND THAT TIME.

THE INITIAL MOTION ESTIMATE IS 320/14…A LITTLE TO THE RIGHT OF THE PREVIOUS FORECAST.  DURING THE PERIOD…THE GLOBAL MODEL GUIDANCE IS IN GOOD AGREEMENT ON THE EVOLVING SYNOPTIC PATTERN.  OVER THE NEXT COUPLE OF DAYS…DANIELLE WILL BE STEERED NORTHWESTWARD TO THE SOUTH OF A NARROW MID-LEVEL RIDGE CENTERED BETWEEN 30N AND 35N. AFTER THAT TIME…DANIELLE WILL TURN NORTHWARD AHEAD OF A LONGWAVE MOVING EASTWARD OFF THE COAST OF NORTH AMERICA.  SOME DIFFERENCES REMAIN IN THE DETAILS OF HOW QUICKLY DANIELLE TURNS NORTHWARD…ANDIF AN ACCELERATION TO THE NORTHEAST WILL OCCUR BY THE END OF THE PERIOD.  HOWEVER…MOST OF THE GUIDANCE HAS SHIFTED TO THE RIGHT FOR THIS CYCLE…WITH THE ECMWF AND UKMET FARTHEST EAST AND THE GFS AND NOGAPS FARTHEST WEST.  THE OFFICIAL FORECAST HAS BEEN ADJUSTED A LITTLE TO THE RIGHT THROUGH 48 HOURS TO ACCOUNT FOR THE INITIAL POSITION AND MOTION.  AFTER THAT TIME…THE FORECAST HAS BEEN ADJUSTED EASTWARD AND FASTER TOWARD THE NEW MODEL CONSENSUS…BUT IS TO THE LEFT OF AND SLOWER THAN MOST OF THE GUIDANCE.

WVUA Meteorologist Richard Scott