Wet and windy subtropical storm possible for Southeast U.S.; Mexico eyes TD-10E
A large low pressure system with heavy rain is expected to develop over Cuba and South Florida on Saturday. The counter-clockwise flow around this low will bring strong winds and heavy rains to much of the Florida coast on Saturday, and these conditions will spread northwards to Georgia by Sunday and South Carolina by Monday. The storm may evolve into a subtropical storm that gets a name by Monday or Tuesday, but the potential location of such a storm is still murky. The extended forecast discussion from NOAA's Hydrometeorological Prediction Center favors a more westerly location, in the eastern Gulf of Mexico, as predicted by the ECMWF model. The GFS model, which puts the storm's center east of Florida, is pushing the weather system that will spawn the subtropical storm too fast to the east. In any case, the exact center location of the storm will not matter that much, since this will be a large, diffuse system that will bring strong winds and heavy rains to a large area of the Southeast U.S. coast, regardless of the exact center location. Portions of the coastal waters from Southeast Louisiana to the Florida Panhandle, as well as from Northeast Florida to South Carolina, are likely to experience sustained winds of 35 - 45 mph Monday and Tuesday. Since the storm is going to get its start as a cold-cored upper-level low pressure system with some dry air aloft, it will probably start out subtropical, with a large band of heavy rain developing well north of the center. Subtropical storms cannot intensify quickly, due to their lack of an organized inner core, and I'm not concerned at present about this storm potentially becoming a hurricane.

Figure 1. Rainfall forecast for the 5-day period ending at 8 am EDT Tuesday, October 11, 2011. The storm system affecting Florida this weekend is expected to bring up to 7 inches of rain along the coast. Heavy rains associated with a strong trough of low pressure are also expected to dump 4 - 6 inches of rain over drought-stricken areas of Texas, Oklahoma, and Kansas. Image credit: NOAA/HPC.
Philippe becomes a hurricane
After 12 days and 49 advisories, Philippe has finally intensified into hurricane, becoming the fifth hurricane of the 2011 Atlantic hurricane season. The fifth hurricane normally arrives on October 7, so this is a very average season for hurricanes, despite the fact it is already the 7th busiest season since record keeping began in 1851 for number of tropical storms--sixteen. Satellite loops show Philippe is a small hurricane with just a hint of an eye. A wide band of clouds to Philippe's northwest is associated with the trough of low pressure that has recurved Philippe to the northeast. By Friday, the trough will bring very high wind shear of 30 - 50 knots, which should cause rapid weakening. Philippe will not trouble any land areas.

Figure 2. Morning satellite image of Philippe. The band of clouds to the northwest of Philippe is associated with a cold front that has recurved Philippe to the northeast.
A double threat to Mexico's Eastern Pacific coast
In the Eastern Pacific off the coast of Mexico, two new tropical cyclones have formed. The one of greatest concern is Tropical Depression 10-E. TD 10-E is currently headed west-northwest, parallel to the coast, but will turn north and then northeast over the weekend as a strong trough of low pressure dives southward over northern Mexico. The computer models have a fairly wide spread for the track of TD-10E, with the region of coast centered on Puerto Vallarta between Manzanillo and Tuxpan at greatest risk of a strike. TD 10-E is under moderate shear of 10 - 20 knots, and shear is predicted to stay in the low to moderate range for the next five days. Ocean temperatures are warm, 28 - 29°C, but the warm waters do not extend to great depth, limiting TD-10E's potential for rapid intensification. Nonetheless, the GFDL model predicts TD-10E will intensify into a major Category 3 hurricane before landfall on Monday on the Mexican coast, and the HWRF model brings the storm to Category 2 strength. The official NHC forecast is less aggressive, bringing TD-10E to Category 1 strength, but this is conservative, and I put the odds at 30% that the storm will be a Cat 2 or stronger at landfall. One possible impediment to development may be TD-10E's close proximity to Tropical Storm Irwin to the west. Upper-level outflow from Irwin could weaken TD-10E, and the two storms may compete for the same moisture. Regardless of TD-10E's strength at landfall, the storm will bring very heavy rains to the Mexican coast capable of causing dangerous flash floods and mudslides, beginning on Monday.
Once TD-10E has made landfall, Mexico may need to concern itself with Tropical Storm Irwin, which is gathering strength farther to the west. Irwin is also moving to the west-northwest, and will also be turned north and then northeast towards the coast of Mexico this weekend by the same trough of low pressure expected to affect TD 10-E. The longer range computer forecast models show Irwin could make landfall on the Mexican coast late next week.
European heat wave: hottest October temperatures on record for the UK
The British Isles have been basking in an unprecedented October heat wave this week, which has brought the warmest temperature ever measured in the UK for the month of October. On Oct. 1, a reading of 29.9°C (85.8°F) was recorded at Gravesend, Kent, beating the previous UK October record of 29.4°C (84.9°F) at Cambridgeshire on Oct. 1, 1985. Wales also broke their warmest temperature for October with a 28.2°C (82.7°F) at Hawarden, Flintshire. Edinburgh, Scotland reached 24.7°C (76.4°F) for Scotland's warmest temperature in at least 50 years. Thanks go to wunderground's weather historian Christopher C. Burt. His latest post is on record hurricanes of the past in the Pacific Ocean.
Jeff Masters
Reader Comments
Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 — Blog Index
Looks like there is some nice pops right off shore headed towards you like what you've already seen. Gonna be a mess later I think.
28.3n59.7w, 28.8n58.7w, 29.3n57.1w are now the most recent positions
Starting 6Oct_6amGMT and ending 7Oct_6amGMT
The 4 western line-segments represent HurricanePhillippe's path,
the easternmost line-segment is the straightline*projection for 7Oct_6amGMT,
the island blob at 38.565n28.779w-HOR is the endpoint of the 7Oct_12amGMT
straightline*projection connected to its nearest airport,
and the island blob at 58.529n6.261w-syy is the same* for the 6Oct_6pmGMT.
(* The straightline projections and their endpoints are freshly derived from the most recent positions)
Using straightline projection of the travel-speed&heading derived from the
ATCF coordinates spanning the 6hours between 12amGMT then 6amGMT :
H.Phillipe's travel-speed was 17.2mph(27.6k/h) on a heading of 70degrees(ENE)
H.Phillipe was headed toward passage over AlMancouriya,Morocco ~6days22hours from now
For a look at the branching straightline projections and other info, copy&paste 26.5n60.8w-27.4n60.4w, 27.4n60.4w-28.3n59.7w, 27.4n60.4w-58.529n6.261w, syy, 28.3n59.7w-28.8n58.7w, 28.3n59.7w-38.565n28.779w, hor, 28.8n58.7w-29.3n57.1w, 28.8n58.7w-33.75n7.31w, cas into the GreatCircleMapper for more info.
The previous mapping for 7Oct_12amGMT
NWS rain chances:
Today: 40
Tonight: 50
Saturday: 70/winds at 20-25
Sat. Night: 60
Sunday: 60
With the heavy rainfall possible starting Saturday.
That's what I was talking about...the Evacuation Immediate for Illinois, check the NWS weather map you'll see.
Tonight...you mean today, but yeah I see where you're getting. It's about to get rather nasty we'll just have to see. You think we'll get flash flooding?
Rather calm at the moment, but the skies look beautiful.
Yeah... I think it will be later in the day though.
NWS only has us for 40 percent today right now.. so I think it will be hit and miss... the real fun will be tomorrow.
and yes, one of the local TV stations will find an intersection with three feet of water I think.
Clear skies this morning...
Really pulling some fast stuff across your part of the peninsula.
Nice summary on your blog. I'm spending a week in Key West 10/15-22. That's well into the future, but do you have any comfort in predicting what type of week that might be based on any of the weather models at this point?
Philippe is a good-looking storm, after struggling to maintain itself for almost two weeks. Finally, it has become a hurricane, and may, MAY be hitting its peak now. However, the NHC stated in the 5AM advisory that T#'s were around 4.5...They are 4.8 now, or close to Category 2 strength. The NHC will probably keep 90 mph, or they may go with 100 mph. It would be nice to see Philippe become a Category 2 hurricane...
I have no school today.
2011: Arlene, Bret, Cindy, Don, Emily, Franklin, Gert, Harvey, Irene, Jose, Katia, Lee, Maria, Nate, Ophelia, Philippe.
2005: Arlene, Bret, Cindy, Dennis, Emily, Franklin, Gert, Harvey, Irene, Jose, Katrina, Lee, Maria, Nate, Ophelia, Philippe, Rita, Stan, Tammy.
FOR TOMORROW AND SUNDAY...SYNOPTIC PATTERN BECOMES MORE
COMPLICATED. THE SURFACE LOW IN THE CARIBBEAN BEGINS TO TRACK
NORTHWARD. THE TRACK OF THE SYSTEM THROUGH SUNDAY IS STILL
UNCERTAIN BUT GENERAL CONSENSUS FAVORS THE ECMWF.
REGARDLESS...PLENTY OF MOISTURE WILL SURGE NORTHWARD ALONG A
BOUNDARY THROUGH THE WEEKEND. GENERALLY...THERMODYNAMICS DO NOT
LOOK IMPRESSIVE FOR THUNDERSTORMS BUT WILL SUPPORT NUMEROUS
SHOWERS WITH ISOLATED THUNDERSTORMS BOTH SATURDAY AND SUNDAY.
EASTERLY WINDS WILL INCREASE DURING THE AFTERNOON/EVENING HOURS TO
AROUND 15-20 MPH WITH HIGHER GUSTS. LOCALLY HEAVY RAINFALL WILL BE
POSSIBLE. HOWEVER...CURRENT GUIDANCE KEEPS THE HIGHEST AMOUNTS
INLAND THROUGH THE EAST COAST.
Sheena Parveen.......gettin it done!
Regardless of whether we see develop or not, Florida will have a very wet weekend, with much of the Southeastern USA experiencing the same as we head into next week. However, I do believe there is a good chance of us seeing Subtropical development over the next few days.
That would be me.
I need an airboat.
42 Hours
Excellent post there.
It's so good to know that there are sensitive folks putting forth their views on the AGW debate.
I hope that with posts like yours, some of the Unbelievers will start to think again about the future and do something about it by coming out on the side of Science.
It's dumping rain in Port St. Lucie and Fort Pierce. Miserable drive to work this morning. Medians full of water and ditches filling fast. Gonna be lots of flooded roads later today if this keeps up which will make the drive home after work a mess. It trained rain in all night and the radar still shows lots more heading this way. Any thoughts on where the low is going to form? I am looking at all that convection down around the Keys and over Cuba. Also see another bit in NE Gulf. Guess we will just have to continue to wait and watch.
LONG TERM (SUNDAY NIGHT-THURSDAY)...ECMWF CONTINUES TO BE THE
PREFERRED MODEL IN THE EXTENDED PERIOD AS THE GFS REMAINS TOO FAR
EAST WITH SURFACE LOW DEVELOPMENT AND TRACK. STRONG SURFACE HIGH
PRESSURE WILL HOLD ALONG THE MID ATLANTIC COAST MONDAY WITH AN
AREA OF LOW PRESSURE DEVELOPING OVER THE SOUTHEAST GULF OF
LIKELY A HYBRID TYPE STORM SYSTEM. TIGHT PRESSURE
GRADIENT BETWEEN THE HIGH TO THE NORTH AND LOW TO THE SOUTH WILL
ENHANCE WINDS OVER THE FORECAST AREA AND ADJACENT COASTAL WATERS.
HIGH DEGREE OF UNCERTAINTY REMAINS WITH EVOLUTION AND TRACK OF THE
AREA OF LOW PRESSURE...BUT DRY SLOT MAY DEVELOP EAST OF THE CENTER
WHICH COULD BE OVER WEST CENTRAL AND SOUTHWEST FLORIDA ON
MONDAY...WITH A CHANCE OF SHOWERS AND SLIGHT CHANCE OF
THUNDERSTORMS. AS THE SURFACE LOW TRACKS NORTH OVER THE EASTERN
GULF MONDAY NIGHT AND TUESDAY...INCREASING SOUTH TO SOUTHWEST FLOW
WILL ALLOW NUMEROUS SHOWERS AND A FEW THUNDERSTORMS TO DEVELOP
OVER THE COASTAL WATERS WHICH WILL MOVE LOCALLY ONSHORE.
POSSIBILITY FOR TRAINING OF HEAVY RAIN BANDS WHICH COULD CAUSE
LOCALIZED FLOODING. SURFACE LOW EXPECTED TO MOVE TOWARDS THE BIG
BEND AREA LATE TUESDAY NIGHT WITH DECREASING CHANCE OF RAIN ACROSS
WEST CENTRAL AND SOUTHWEST FLORIDA ON WEDNESDAY. DEPENDING ON THE
STRENGTH OF THE SURFACE LOW...SOUTH TO SOUTHWEST WINDS OVER THE
EASTERN GULF WILL CAUSE WATER TO PILE UP CREATING A THREAT OF
COASTAL FLOODING. ALTHOUGH TIMING IS STILL VERY MUCH IN
DOUBT...ATTM IT APPEARS BEST CHANCE WILL BE TUESDAY AND TUESDAY
NIGHT. IN THE WAKE OF THIS STORM SYSTEM...A STRONG U/L DISTURBANCE
WILL APPROACH THE SOUTHEAST U.S. ON THURSDAY WITH CONTINUED
SOUTHWEST FLOW OFF THE GULF OF MEXICO AND A CHANCE OF SHOWERS AND THUNDERSTORMS.
I posted a link earlier this morning... you can really see it well on the water vapor imagery.
signs of activity in Florida Straits.
Link
Have to drive through and just northeast and west of Orlando today.
I hope the weather holds until I get out of there.
I hear ya on the drive to work, port saint lucie blvd and us1 was not a good time this morning. Looks to be a real wet weekend here in ecfl.
Link
Pretty good puttin' the pieces together there.
Y'all have had 4 inches of rain over the last couple days, and this entrenched mess is only making it worse.
And in the last couple of images on the water vapor loop that area is looking like it's trying to get hooked up:
Link
Starting to look sporty on rainbow as well:
Link
That drive is never good no matter what the weather! LOL
Normally I would trust the local stations here but I would disregard them right now, the NWS has shown that the general consensus is in the the Southeastern gulf, which is strange because the local weather stations usually are mostly in agreement with the NWS on overall setup. The GFS is the only model insisting on an East Coast development, and it hasn't been very consistent in its placement. The ECMWF however has been very consistent on intensity and placement of the low in the Southeastern gulf. Furthermore, additional models have trended west with time.
I agree, it appears that is the upper trough carving out into an upper low. You can already see how the environment has already become more favorable for convection around Florida. Also, noticed the upper trough and vorticity max is diving south. The surface reflection generally occurs south of that. The GFS has the upper low placement to far east as well.
Going to be interesting to watch for sure.
Viewing: 401 - 451
Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 — Blog Index