Low Pressure in Gulf of Mexico

[ronjon]

Heavy rainfall really starting to fill in the FL peninsula. Lowest pressure off Ft Myers now. Can make out the circulation in the RAD. It's a cold core low pressure but that doesn't mean it can't deepen to tropical storm strength pressure. Heck, we've already had tropical storm strength gusts along the FL northeast coast the last 24 hrs.

http://radar.weather.gov/ridge/radar.php?rid=TBW&product=N0R&overlay=11101111&loop=yes

[Bailey1777]

Hey aric! Whats the latest in your opinion.

[ronjon]

From NWS Melbourne AFD:

HYDROLOGY...BEST CHANCES FOR HEAVY AND PERSISTENT RAINFALL WILL
CONTINUE TO BE ALONG THE COAST AND OVER THE AREA NORTH AND WEST OF
THE I-4 CORRIDOR WHERE STRONG ONSHORE FLOW WILL ENHANCE CONVERGENCE
ALONG THE COAST WITH MODERATE TO HEAVY SHOWERS AND RAINBANDS
CONTINUING. THESE AREAS HAVE ALREADY SEEN PLENTY OF RAIN...
ESPECIALLY OVER VOLUSIA AND INTO NORTHERN LAKE COUNTY WHERE 5 TO
8 INCHES WAS OBSERVED ACROSS MANY AREAS SINCE YESTERDAY. AN AREAL
AVG OF ADDITIONAL 2 TO 4 INCHES ARE POSSIBLE INTO TOMORROW WHICH
WOULD LIKELY CAUSE FLOODING CONCERNS...OR AGGRAVATE ANY FLOODING
THAT DEVELOPS THIS AFTN/EVENING.

[tina25]

Can you take a picture and post it? I'm interested to see what the sky looks like!

I'm in the Naples/Ft. Myers area and there is zero wind here. Clouds inland and north of me look very bizarre.

This is looking towards the north. I was out running errands earlier and I noticed how dark it looked inland. Just started pouring here.

[ronjon]

Pressure falling at Ft Myers with lowest pressure. West wind at Naples.

FORT MYERS PTSUNNY 80 63 55 CALM 29.75F

[Aric Dunn]

Hey aric! Whats the latest in your opinion.

well, there is clearly a circualtion closing off just off the west coast of florida that is diving SW. this low along with the upper low will migrate west over the next few days all the while bringing a lot of rain to Florida and the SE. there is some potential for this to transition to a sub-tropical system as it moves over the warm gulf loop waters. it will be a slow mover so there is plenty of time for things to change. some factors are the placement of the low center in relation to the upper low if the system is stacked then it will be harder to see some sort of sub tropical development . on the other hand as of right now they are not stacked at least not vertically aligned which means the surface low may end up in a more favorable area to see some development. so we have watch and see how it plays out, we are not going to see anything new today forecast wise except the development of a low center that can at least be tracked and inputted into the models which hopefully gives us a better idea of what may happen with the upper low and surface low. other than that just have to stay enjoy the rain and TS gust ( depending on where you are) ...

[dolebot_Broward_NW]

Facing west from 595/sr84/turnpike. (Actually in the port95 industrial area on 30th)

Looks like this on the radar:

[floridasun78]

it cloudy to my west i near mia airport but no rain here it look like system is going affect more of central fl and north and south fl one weatherman say he see dryair moving to north from keys

[AdamFirst]

Picture from Port Saint Lucie

http://img.photobucket.com/albums/v207/ ... 0_0726.jpg

It's been like this all day...when it's not gray and wet it's just gray

[jlauderdal]

By jfaul4820 at 2009-05-19

[KWT]

Yep does look like a circulation has formed given the west wind that has been observed, also still throwing quite a lot of cells across Florida which is good news.

[Aric Dunn]

its really starting to deepen .. pretty fast now..

[dixiebreeze]

The Ocala area has been slammed with torrential rain and high winds Monday and today. Almost impossible to drive.

[NEXRAD]

The Gulf system has an organizing surface low per visible imagery and surface observations. Pressures are down to around 1006 to 1007 mb near and offshore Fort Myers at present with pressure falls of 1 to 2 mb per hour since 1 PM (per the Venice C-MAN and Fort Myers station). Despite these pressure falls, the developing circulation is devoid of nearby deep convection. A quick look at IR satellite shows a winter-like non-tropical low pressure system appearance with mostly shallow-topped moderate convection extended in a large shield north and east of the mid-level circulation (which is the cut-off low from the previous trough). Dry air is punching deep into the south and southeast quadrants of the mid-level circulation, which is resulting in diminished convective activity across the Keys and much of South Florida, exception being scattered cells across interior South Florida. This South Florida activity is mostly diurnally driven. Otherwise, dynamically forced convection is occurring mostly north and east of a line from Fort Pierce to Brooksville and then south of the I-10 corridor through North Florida/Ern Panhandle region. Rainfall rates have been unimpressive, mostly 0.25in/hr or less, save with a few isolated heavier cells mostly across parts of S & SW Florida.

The present developing Gulf low lacks tropical characteristics. With the cold core low aloft, there will need to be considerable mid-level airmass modification before a fully warm-cored system can take root. Over the next day or two, a subtropical storm may develop, but overall effects for land interests will be comparable to most winter Gulf low systems.

- Jay

[Aric Dunn]

The Gulf system has an organizing surface low per visible imagery and surface observations. Pressures are down to around 1006 to 1007 mb near and offshore Fort Myers at present with pressure falls of 1 to 2 mb per hour since 1 PM (per the Venice C-MAN and Fort Myers station). Despite these pressure falls, the developing circulation is devoid of nearby deep convection. A quick look at IR satellite shows a winter-like non-tropical low pressure system appearance with mostly shallow-topped moderate convection extended in a large shield north and east of the mid-level circulation (which is the cut-off low from the previous trough). Dry air is punching deep into the south and southeast quadrants of the mid-level circulation, which is resulting in diminished convective activity across the Keys and much of South Florida, exception being scattered cells across interior South Florida. This South Florida activity is mostly diurnally driven. Otherwise, dynamically forced convection is occurring mostly north and east of a line from Fort Pierce to Brooksville and then south of the I-10 corridor through North Florida/Ern Panhandle region. Rainfall rates have been unimpressive, mostly 0.25in/hr or less, save with a few isolated heavier cells mostly across parts of S & SW Florida.

The present developing Gulf low lacks tropical characteristics. With the cold core low aloft, there will need to be considerable mid-level airmass modification before a fully warm-cored system can take root. Over the next day or two, a subtropical storm may develop, but overall effects for land interests will be comparable to most winter Gulf low systems.

- Jay

agreed... although not sure where you were talking about for rain rates? i have had nearly 9 inches since yesterday afternoon and areas just to my north have soon a foot of rain.....

[floridasun78]

it look to me that central fl and north fl will be affect by non tropical low

[NEXRAD]

agreed... although not sure where you were talking about for rain rates? i have had nearly 9 inches since yesterday afternoon and areas just to my north have soon a foot of rain.....

Rain rates - not rain totals. I've discussed present conditions and trends across Florida and the nearshore areas. Per radar rainfall estimates over the past few hours, there have been few locations receiving above 0.25 inch per hour. I will not say that rain totals are unimpressive. Indeed, most locations across the state have 2 to 5 inches already. The current rain totals are comparable to what many tropical systems produce.

- Jay

[Recurve]

Well despite some dark clouds earlier, the Keys have pretty much cleared out and are now mostly sunny, at least in the upper region. We have light winds (<10kts.) from the south. I was really hoping for another soaking....last night we got pounded, but things seem to have moved away. There's a little cell in deep south Miami-Dade and a small cell out in the straits, and that's about it near us.

[cycloneye]

18 UTC Surface Analysis shows a 1009 mb low SW of Naples.

[HurricaneGirl]

agreed... although not sure where you were talking about for rain rates? i have had nearly 9 inches since yesterday afternoon and areas just to my north have soon a foot of rain.....

Rain rates - not rain totals. I've discussed present conditions and trends across Florida and the nearshore areas. Per radar rainfall estimates over the past few hours, there have been few locations receiving above 0.25 inch per hour. I will not say that rain totals are unimpressive. Indeed, most locations across the state have 2 to 5 inches already. The current rain totals are comparable to what many tropical systems produce.

- Jay

Hi Jay! Long time no see.. Were I live we've had about 3-1/2 to 4" of rain. Do you think this will become Tropical?