Another Inland Tropical System Born!

[Stephen Levine]

The following Summary is on our NWS site this evening.
It's well stated and I believe has the potential to re-open conversation about inland tropical systems.

It appears that this occurs more frequently than has been credited in the past.

I noted the dramatic banding on radar today as well as the winds with no obvious pressure gradients due to any nearby or enroaching high pressure system.

It also brings to mind the cyclone with eye that occured in OK a couple years ago, as well as how a very windy IKE tracked all the way up the Ohio Valley, doing damage along it's entire path.

Any thoughts?

NATIONAL WEATHER SERVICE FORT WORTH TX
835 PM CDT WED SEP 16 2009

.UPDATE...
THE LOW PRESSURE SYSTEM CONTINUES TO WANDER WESTWARD...BUT WILL
BEGIN TO DROP SOUTH TONIGHT AND TOMORROW. THIS LOW IS ESSENTIALLY
ACTING AS A REMNANT TROPICAL CYCLONE...WITHOUT THE FANFARE OF EVER
BEING A TROPICAL SYSTEM WITH A NAME. THE LOW IS VERTICALLY
STACKED...FORMED IN A LOW SHEAR ENVIRONMENT...AND HAS A WARM-
CORE...MEANING THICKNESS VALUES/TEMPERATURES IN THE CORE OR CENTER
OF THE LOW ARE WARMER THAN THE SURROUNDING ENVIRONMENT.

BECAUSE OF ITS WARM CORE DYNAMICS...LAPSE RATES ARE LOW AND
INSTABILITY BECOMES LIMITED WITHOUT AN ACCESS TO A SUSTAINED
SOURCE OF HIGH THETA-E AIR. THIS IS WHY TROPICAL CYCLONES REQUIRE
WARM OCEAN WATERS...BECAUSE IT SUPPLIES AN ENORMOUS SOURCE OF LOW
LEVEL INSTABILITY FOR CONTINUOUS DEEP CONVECTION. OUR CURRENT WARM
CORE LOW FORMED OVER LAND AND HAS WRAPPED STABLE CONTINENTAL AIR
ALL THE WAY AROUND THE CIRCULATION. THUS...THE INSTABILITY IS
WEAK...AND THUNDERSTORMS HAVE BEEN NEARLY NON-EXISTENT...WITH
SHALLOW CONVECTION DOMINATING. STILL...WITH JUST THIS MEAGER
BAROTROPIC INSTABILITY...WE HAVE A SURFACE LOW CENTER OF 1007
MB...A CURIOUS EFFECT OF PRESSURE FALLS AND STRONGER NORTH WINDS
TONIGHT...AND LASTLY A RADAR PRESENTATION SHOWING IMPRESSIVE
SPIRAL BANDING.

ALL IN ALL...THE FORECAST WILL BE UPDATED TO RAISE WINDS AND LOW
TEMPS A BIT. WILL KEEP THE CURRENT POP AND QPF CONFIGURATION
WITH BEST CHANCES OF RAIN IN THE EAST WITH AVERAGE QPF OF AN INCH
OR SO. ONE THING TO NOTE...IS THAT BECAUSE WE ARE ESSENTIALLY
DEALING WITH A REMNANT TROPICAL CYCLONE...THERE IS A POSSIBILITY
OF CORE RAINS TONIGHT NEAR THE CENTER. CONTEMPLATED A SMALL FLASH
FLOOD WATCH OVER THE EASTERN ZONES...BUT AGAIN...THE COMPLETE LACK
OF HIGH THETA-E AIR AVAILABLE TO THIS SYSTEM WILL INHIBIT DEEP
CONVECTION AND THUS THE POTENTIAL FOR FLASH FLOOD PROVOKING
RAINFALL.

TR.92

 

[Jared Thompson]

Tonight we are getting winds at 29 mph here in the metroplex got to love inland rain bands.

 

[Mike Kovalchick]

Probably one of the best examples of an inland tropical system was "Hurricane Huron" back in September of 1996:

http://en.wikipedia.org/wiki/Hurricane_Huron

It had winds of up to 67 mph, a 19 mile diameter eye like feature, central pressure of 993 mb, produced up to 4" of rain, and had other tropical characteristics; much of it due to the warm waters of Lake Huron.

 

[Adam Lucio]

That is very interesting to read. I saved this image from GR3 yesterday and posted it on my facebook with the caption: "A hurricane over TX/AR/OK? Nah, just a persistent closed low that wont go anywhere because 2009s weather pattern sucks."

 

[Joshua Nall]

Whatever you want to call it, it has been a very efficient rain producer for this area. We were in the "eye" for most of the day yesterday and only received .10" of rain in the form of a very heavy mist. I have a lawn care business and this will be the first time in five years that I have missed four straight week days of work do to rain. Tomorrow may be a rain out as well. I've received about 7" total.

Josh