TROPICAL STORM FORMATION: IDA, AOI 20%
ALL forecasts contained on this site, are based on my analysis and knowledge of various forecast tools, including information contained in NHC products, and are not copies from any other entity.
*NOTE: In the TROPICAL STORM FORMATION line above, probabilities are for during the next 5 day period. My personal probability will be listed as either NONE, MONITORING or PROBABLE. This does not necessarily mean something will develop, but that certain forecast conditions are likely to be present, favoring development. Once NHC products become available, then the appropriate probability and percentage will be used.
Please refer to the link for the Storm Prediction Center in the box at the top of the page, just below the Hurricane Hunter graphics.
For those who have donated to my site, your help has been greatly appreciated. For those not aware, donations to my site help me offset my personal out of pocket expenses…such as some of the model maps you view on here, are only available due to my subscription to the corresponding site. The F5 Data maps I post, also another out of pocket expense (monthly subscription). Updates to software (weather related), and costs for my domain name are also out of pocket to me. Any help you provide is immensely appreciated! Although it may seem I am not here and working in support of your donation, I have to work my forecasting time around my ever changing work schedule.
Current Storm Total for 2015:
TOTAL STORMS: 9
INTENSE HURRICANES: 1
U.S. LANDFALLS: 2
StormW’s Seasonal Forecast:
TOTAL STORMS: 8
INTENSE HURRICANES: 1
Good evening everyone!
Tropical Depression IDA is still hanging on…BARELY. As of the 5:00 p.m. advisory from the NHC, the following was available on the depression:
5:00 PM AST Fri Sep 25
Location: 22.5°N 45.5°W
Moving: NW at 6 mph
Min pressure: 1007 mb / 29.74 in
Max sustained: 30 mph
Satellite imagery indicates the LLC is again, exposed to the west of the minimal convection. This has been caused primarily by westerly shear throughout the day. However, the most recent wind shear product indicates this has relaxed to about 10-15 knots over the system.
CIMSS IDA WIND SHEAR
Based on these shear values, I am leaning towards dry air being the main culprit at the moment for the ragged appearance.
Based on the current shear forecast, and premise of continued dry air intrusion, I concur with the NHC in that the depression should become a remnant in approximately 24 hours.
Based on analysis of the forecast steering pattern, the depression should make a turn toward the WSW in about 24 hours. This is shown in the NHC tracking map, and concurs with the 18Z dynamic guidance, inline with the dynamic consensus.
ATCF 18Z DYNAMIC GUIDANCE
Elsewhere, I continue to monitor the trof of lower pressure near the Nicaragua/Honduras area. Satellite loop imagery gives a fairly good picture of some cyclonic turning. Based on the station plot overlays, there is a noted wind shift over the Yucatan Peninsula, however there is no closed circulation at this time, and the strongest vorticity was located in the Gulf of Honduras.
CIMSS 850 MB VORTICITY
Global models are still hinting at some type of low in about 24-36 hours in the southern GOMEX, however on the latest runs, modeling is pretty much all over the place as far as location and strength. When the models get this way with their solutions, I opt to monitor for development in real time, focusing mainly on the forecast upper level pattern, and forecast steering. So, at the moment, no, I do not know where “it” is going to go, as “it” is not here yet…so until there is actually development, it’s pretty useless and somewhat foolish to try and pinpoint any exact “location” However, based on analysis of the recent forecast steering layers maps, the suggestion is, the “center” should remain east of Louisiana, and could focus more eastward from MS to the western FL. Panhandle.
Again, as far as intensity, it is going to be better to deal with this in a real time scenario. Upper level winds may only be marginal over the GOMEX, as a sharp trof is still forecast to be in place over southern TX, with the predominant flow over the Gulf being from SW to NE. One thing I will mention on this…the further west this low is, the more affect wind shear will have on it. IF this moves further east, closer toward FL., the current wind shear forecast and 200 mb streamline pattern does indicate shear to relax over a narrow area, with a small anticyclonic upper feature noted. In any case, based only on what the models are showing, this should not amount to anything significant. The GFS 10M wind forecast indicates 20 to possibly 30 knot winds at the most, over a small area. Again, I’ll have a better idea once we see “something” develop.
Elsewhere, Tropical Storm formation is not expected during the next 7 days.
Have a blessed evening!
T. F. “STORM” WALSH III
GMCS, USCG (ret)
METEOROLOGIST / HURRICANE SPECIALIST /SEVERE WEATHER SPECIALIST
MEMBER WEST CENTRAL FLORIDA AMS