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wxdata wrote:It seems that the urban heat island is having its effect on the line now in Harris

I'm sorry, but I'm not sure what you are referring to?

Very nice lightning and heavy rain the past 20 minutes. Finally recieving a good thunderstorm here...

Nice light show and rain over here too. I'm really happy to see this.

Mr. T wrote:

wxdata wrote:It seems that the urban heat island is having its effect on the line now in Harris

I'm sorry, but I'm not sure what you are referring to?

Theory mostly. Some say the heat from the city can either enhance or decrease showers (depending on atmospheric conditions.)

Lightning was excellent tonight.
http://s900.photobucket.com/albums/ac20 ... C14154.flv

Well, this round is about to come to a close.
The next few days could prove to be very interesting.

Off to bed...

Not much in the way of rainfall last night for my lawn, but anything is better than nothing. While HGX is thinking the atmosphere has been worked over by last night's MCS, the Upper Low/trough appears to be located just to the NW of Metro Houston this morning and showers/storms are beginning to fire off near College Station and point E. We will see if an organized area of storms continue to develop near that feature. Fingers crossed for more rainfall.

Was quite a lightening show here in central Texas. I saw something I don't think I've seen before. It was a cloud to ground double strike with the bolts about a mile apart (hard to tell for sure) from each other, and nearly parallel to each other. Would have been a great photo.

HPC has updated concerning heavy rainfall. The area of showers/storms continue to increase in areal coverage and intensity as a cold pool associated with a nearly stationary Upper Low remains just to our N and W...

EXCESSIVE RAINFALL DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
910 AM EDT THU JUN 03 2010

...VALID 15Z THU JUN 03 2010 - 12Z FRI JUN 04 2010...
...REFERENCE AWIPS GRAPHIC UNDER...DAY 1 EXCESSIVE RAINFALL...



ERN TX/LA...
U/A DATA THIS MORNING SHOWS A WELL DEFINED MID/UPR LEVEL CIRC OVER
ERN TX STILL DRIFTING VERY SLOWLY EWD. CONVECTION HAS STARTED TO
REDEVELOP AROUND THE CIRC CENTER THIS MRNG..THOUGH REMAINS MORE
ENHANCED IN TO THE EAST ACRS SRN LA IN AREA OF BETTER
INFLOW/CONVERGENCE AND HI PWS IN EXCESS OF 2 INCHES. WHILE FFG
VALUES ACRS THIS AREA ARE QUITE HIGH...THE VERY SLOW MOVEMENT OF
THE UPR LOW COUPLED WITH HIGH MSTR AND POTNL INSTABILITY COULD
LEAD TO SOME ISOLD VERY HEAVY RAINFALL RATES. AS A RESULT COULD
NOT RULE OUT SOME ISOLD RUNOFF PROBLEMS HERE WHERE COULD SEE SOME
QUICK 2 TO 4 INCH RAINS IN A COUPLE HOURS..ESPECIALLY IN AREAS
WHERE CELLS REPEAT.

SULLIVAN

So where is this low forecasted to go. Any chance it gets off shore, it looks like its headed south now. If it gets off shore then what?

gregco31 wrote:So where is this low forecasted to go. Any chance it gets off shore, it looks like its headed south now. If it gets off shore then what?

Guidance has been a bit murky concerning the Upper Air feature. Some models suggest that the Upper Low will meander around the Western GOM through the weekend into early next week. It certainly does not appear it will be moving anywhere too fast.

Interesting update from Jeff...

Carefully watching stacked circulation over SE TX late this morning. Warm core center has developed with excessive rainfall focused on the northern side of the surface low noted near Huntsville. Circulation appears to be taking on warm core features similar to a tropical cyclone where excessive rainfall develops in bands during the day and near the core during the night. Will need to keep a close eye on this slow moving/meandering system for the next 24 hours or so.

SATELLITE PRECIPITATION ESTIMATES..DATE/TIME 06/03/10 1642Z
SATELLITE ANALYSIS BRANCH/NESDIS---NPPU---TEL.301-763-8678
LATEST DATA USED: GOES-13 1615Z JBN

SATELLITE ANALYSIS AND TRENDS...LATEST GOES WV IMAGERY SHOWS A MID/UL
DISTURBANCE OVER SE TX THAT IS SLOWLY MOVING E. DEEP MOISTURE IS BEING
PULLED INTO THIS SYSTEM FROM THE GULF OF MEXICO AS SEEN BY A VERY SMALL
MOISTURE PLUME OBER SE TX/WRN LA. PWATS IN THIS AREA ARE AVERAGING NEAR
2.0" ACROSS SE TX/WRN LA WHICH IS ABOUT 150% OF NORMAL FOR THIS TIME
OF YEAR. IR IMAGERY SHOWS A DEVELOPING COMMA HEAD CLOUD FEATURE ON THE
NRN/NERN SIDE OF THE DISTURBANCE WHERE CLOUD TOPS ARE SHOWING A STRONG
COOLING/EXPANDING TREND. THESE COOLING/EXPANDING CLOUD TOPS ARE ASSOCIATED
WITH CONVECTION THAT APPEARS TO BE ORGANIZING INTO SINGLE WSW/ENE ORIENTED
BAND THAT EXTENDS INTO NRN LA. THIS BAND IS THEN BEING PULLED TOWARD THE
MID/UL DISTURBANCE. THIS COULD LEAD TO SOME TRAINING CONVECTION ACROSS THE
DISCUSSION AREA WITH THE HEAVIEST RAIN BEING CONCENTRATED INTO A SINGLE
CONVECTIVE BAND EXTENDING FROM MILAM COUNTY IN TX ENE TO JACKSON/WINN
PARISHES IN LA THE NEXT FEW HRS. RAIN FALL RATES MAY EASILY BE IN THE
1-1.5"/HR RANGE WITH THIS CONVECTION BASED ON THE AVAILABLE MOISTURE
AND COOLING/EXPANDING TAKING PLACE IN IR IMAGERY. THE CONVECTION SHOULD
PERSIST FOR THE NEXT SEVERAL HRS AS THE MID/UL DISTURBANCE CONTINUES TO
TAP INTO THE DEEP MOISTURE IN PLACE OVER THE REGION. THIS SHOULD RESULT
IN MOD/HVY RAIN ACROSS PARTS OF SE TX/WRN LA.


SHORT TERM OUTLOOK VALID 17Z-20Z...MEDIUM CONFIDENCE FACTOR IN THE SHORT
TERM OUTLOOK BASED ON RECENT TRENDS IN SATELLITE IMAGERY. CLOUDS TOPS
ARE SHOWING A GOOD COOLING/EXPANDING TREND IN IR IMAGERY SUGGESTING
THAT THE COMMA HEAD FEATURE ASSOCIATED WITH THE MID/UL DISTURBANCE IS
BECOMING BETTER ORGANIZED. RAIN RATES ARE PROBABLY INCREASING AS WELL
AS CONVECTION BECOMES ORGANIZED INTO A BAND FEATURE. THIS SHOULD ALLOW
FOR A SWATH OF HVY RAIN ACROSS PARTS OF SE TX/WRN LA WHERE THIS BAND
SETS UP AN PERSISTS FOR A TIME.

I agree with Jeff's update. I was thinking the same with impressive satellite image. This may become a very impressive
tropical-like rain event before its all said and done.

srainhoutx wrote:

gregco31 wrote:So where is this low forecasted to go. Any chance it gets off shore, it looks like its headed south now. If it gets off shore then what?

Guidance has been a bit murky concerning the Upper Air feature. Some models suggest that the Upper Low will meander around the Western GOM through the weekend into early next week. It certainly does not appear it will be moving anywhere too fast.

Katdaddy wrote:I agree with Jeff's update. I was thinking the same with impressive satellite image. This may become a very impressive
tropical-like rain event before its all said and done.

That was kind of why I was asking earlier what happens if this gets offshore. Could it become an Allison type event, obviously not to that magnitude but with no clear steering pattern what prevents it? I can't imagine all this sun outside is a good thing right now.

Becoming a bit concerned for the potential of some training storms to the SW along the 59 Corridor moving slowly ENE. Folks in Ft Bend and Harris Counties may need to keep an eye out for some heavy rainfall rates.

Recieving another round of heavy rain right now

A very interesting setup taking place this afternoon

Heavy tropical rains in NW Harris County. My yard has finally received some beneficial rainfall.

Hi all,

Looks like the low is centered closer to far NW Harris County me to. Even the HPC graphic shows the "L" just west of Houston so I wonder where "Hunstville" came from in the NWS discussion/analysis.

Anyway, this system is practically stalled now so it could be a long/wet night for the metro Houston area and across most of SE Texas. This is one should be watched carefully...