Will Tropical Season Ever End??
Tropical Depression 24 has formed in the Caribbean. It is near Jamaica and drifting very slowly to the west. The tropical intensity models bring TD 24 to Hurricane Wilma in just a few days, in fact some of them bring it to an intense hurricane. The intensity forecast is highly uncertain at this point.
As for the track...our long range forecasting tools bring a cold front through our area by next weekend. This front would provide weakness to move the cyclone northeastward. Right now forecasts have it moving across Florida and out into the Atlantic. As we always say, tropical forecasting is difficult in the long range and this forecast is by no means written in stone. The thing to do is keep it right here with Newscenter 11 as we refine our forecast!
Late Night Update
* The low cloud/fog issue worked out pretty well for our forecast. There were some low clouds and fog, but they dissipated by mid-morning. But, we missed just how far west and south they would develop. Forecasting low cloud/fog placement and development is right up there with summertime convection as one of our big forecast headaches!
* The more things change, the more they stay the same - or at least that's how it seems. Dry weather continues to rule the roost around here through the next 4-7 days. We expect some slightly cooler air in time for the weekend, but the exact extent of the cooldown is still up in the air. The GFS model guidance is 5-7 degrees warmer than our forecast, we are relying more heavily on the European model. Should the GFS turn out to be correct, we may stay warmer than our forecast indicates this weekend. We'll see...
* An interesting link passed along to me tonight by our former weekend meteorologist Derek Kinkade...Pretty cool stuff, hope you find it interesting...
http://www.specwarnet.com/americas/10th_cws.htm
Forecasting Headache
* Even the seemingly "easy" forecast days can offer up some difficult and interesting challenges. Tonight's big issue: will we see low clouds and fog early tomorrow morning? The implications can be rather significant; if the clouds hang tough through much of the day, our high temperature forecast will likely be 10 degrees too warm.
* Step 1. Evaluate the low level moisture around the state. To best do that, look at the difference between the temperature and dewpoint. We call this number the "dewpoint depression." For example, if the temperature is 60 and the dewpoint is 57, the dewpoint depression is 3 degrees. If the dewpoint depression reaches 0 with light or calm winds, fog formation is certainly possible. Our current temperature as of this writing is 60, with a dewpoint of 57 and a dewpoint depression of 3 degrees. Most computer model guidance suggests that the dewpoint depression will fall to 0, which would support the formation of low clouds and fog...
* But, there isn't a lot of soil moisture. Soil moisture can be rather important in formation of fog and low stratus clouds. Also, the computer model guidance suggests that winds will not go completely calm, but a very light breeze will be in place. This breeze helps mix the air up, allowing it to hold more moisture.
* Another piece of evidence we'll evaluate is the latest upper air sounding from Jackson. We look for an "inversion", or an area in the atmosphere where the air is warming as it rises. Normally, air cools as it rises. When we have an inversion, that can trap moisture underneath it and lead to the formation of clouds. There is an inversion present on the latest sounding from Jackson. But, there is also a fairly dry vertical profile in the sounding - which argues against low clouds and fog.
* Bottom line...I believe low clouds and fog will develop as far south as I-20. The best chance will come along the MS/AL state line and points east. Also, low lying areas and places near water will stand a better chance at seeing some fog. However, I think the low clouds and fog will mix (evaporate) out by 9-10 AM, leaving us with ample opportunity for sunshine and subsequent warming into the lower to middle 80's. We'll see how it all works out...
Midnight Madness
* Actually, no madness at all. More dry weather, relatively calm conditions. Temperatures for the next couple of days will stay a few degrees above normal. As much as we need it, we don't appear to have any significant chance of appreciable rain. A weak front will push through late Thursday or early Friday, bringing a reinforcement of slightly cooler and drier air for the weekend. Highs Saturday and Sunday will likely stay in the upper 70's, with slightly lower humidity.
* How about Vince? The system continues to move northeast towards Portugal, and should weaken as it approaches the coastline. This is a very unusual place for a tropical system. Given the active nature of this season, it only seems appropriate.
* We received this e-mail from Gov. Barbour, with an update on the results of the Mississippi Rising event:
October 10, 2005
Dear Friends,
As Governor of the State of Mississippi, I would like to thank you for broadcasting live coverage of the Mississippi Rising event held in Oxford, Mississippi. The benefit was a tremendous success, raising an excess of $15 million that will be used as relief and recovery aid for storm victims across the state.
As you know, Hurricane Katrina has devastated a vast majority of southern Mississippi, and the needs among our citizens are great. While much has been done, our work to rebuild, recover, and renew is just beginning. The steps we must take will be arduous and will take a long time, but working together, we will be successful.
I know this because I know Mississippi. We're a tough and resilient people, but a caring and loving people. Since the hurricane struck, we have been overwhelmed with people who were willing to donate in any way to help us get back on our feet. This help is crucial to our recovery because it will take a joint effort, a magnificent collaboration to rebuild-but rebuild we will. We will rebuild a Mississippi that exceeds anything we've ever known.
In the face of this horrible tragedy, I believe we have the opportunity to make a great state even better, and I am deeply grateful for your help in making this possible. Thank you for broadcasting live the Mississippi Rising fundraising gala. The media is certainly crucial during these times of rebuilding and renewal.
Sincerely,
Haley Barbour
Hurricane Vince Forms
* Hurricane Vince formed this afternoon in the far eastern Atlantic. This will likely weaken soon and will have absolutely no impact on the U.S. This is a very strange place for a hurricane!
HURRICANE VINCE DISCUSSION NUMBER 2
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
5 PM EDT SUN OCT 09 2005
IF IT LOOKS LIKE A HURRICANE... IT PROBABLY IS... DESPITE ITS
ENVIRONMENT AND UNUSUAL LOCATION. MOST AVAILABLE DATA SUGGESTS
VINCE HAS BEEN STRENGTHENING TODAY. IN FACT... THE CIRA INTENSITY
ESTIMATE BASED ON THE EARLIER AMSU OVERPASS NEAR 07Z WAS 50 KT AND
995 MB... SO VINCE WAS PROBABLY EVEN A LITTLE STRONGER THIS MORNING
THAN INDICATED IN THE PREVIOUS ADVISORY. MORE RECENTLY... METSAT-8
IMAGERY REVEALS THAT THE EARLIER RAGGED EYE FEATURE WITH ABOUT
20 N MI DIAMETER HAS CONTRACTED TO 15 N MI AS A BONA FIDE EYE. SOME
ANTICYCLONIC OUTFLOW ALOFT IS NOW DISCERNIBLE AROUND THE DEEP
CONVECTION... ALTHOUGH THE CONVECTIVE TOPS REMAIN A BIT WARMER THAN
IN MOST HURRICANES. SUBJECTIVE AND OBJECTIVE DVORAK T NUMBERS RANGE
FROM 3.5 TO 4.5... WITH THE HIGHER END OF THIS RANGE BASED ON AN
EYE PATTERN. THESE ESTIMATES PROVIDE THE BASIS FOR THE ADVISORY
INTENSITY OF 65 KT. IT IS NOT CLEAR IF THE SURFACE WINDS ARE AS
STRONG AS THE SATELLITE SIGNATURE WOULD NORMALLY SUGGEST...
ESPECIALLY SINCE THE CONVECTION MIGHT LACK SOME VIGOR OVER THE
23-24C SSTS... BUT WE HAVE NO DATA TO CONFIRM OR DENY THE DVORAK
ESTIMATES.
VINCE IS STILL MOVING NORTHEASTWARD BUT NOT VERY FAST... ABOUT
045/5... SO IT COULD MAINTAIN HURRICANE INTENSITY FOR SEVERAL HOURS
WHILE ITS OCEANIC AND ATMOSPHERIC ENVIRONMENT CHANGES LITTLE. VINCE
IS THEN FORECAST TO WEAKEN GRADUALLY AS IT MOVES OVER EVEN COOLER
WATERS AND NORTHWESTERLY SHEAR RAMPS UP. A COLD FRONT IS SEVERAL
HUNDRED N MI NORTHWEST OF VINCE... AND AS THE FRONT CONTINUES ITS
EASTWARD MARCH ACROSS THE NORTHERN ATLANTIC... IT SHOULD PULL VINCE
NORTHEASTWARD AT A GRADUALLY INCREASING FORWARD SPEED. MOST OF THE
DYNAMICAL MODELS AGREE WITH THIS SCENARIO AND SUGGEST THAT VINCE
WILL BE ABSORBED BY THE FRONT IN ABOUT 36 HOURS... BUT IT COULD
TAKE A LITTLE LONGER FOR THE SMALL CIRCULATION OF VINCE TO
COMPLETELY LOSE ITS INDENTITY.
FORECASTER KNABB
