JUNE 2015 -Scattered Showers/Storms To End The Month

[srainhoutx]

The afternoon updated Weather Prediction Center 7 Day Quantitative Precipitation Forecast (Expect Changes daily as the guidance comes into better agreement this week).

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The Climate Prediction Center Day 8+ Analogs are suggesting some interesting analog years and the temperature and precipitation Outlooks continue to advertise near to above normal conditions.

[Paul Robison]

The Weather Predication Center afternoon updated surface charts for Day 3 through 7 suggest a trough across the Western Gulf and possibly an area of low pressure meandering in the Bay of Campeche.

Uh, what?

(latest WPC surface chart. Doesn't look like the same thing.)

[djjordan]

Air you can wear this morning. Summertime in SE Texas .... gotta love it.

[srainhoutx]

The morning water vapor imagery suggests that a trough is sagging S across the Northern Gulf Coast. This trough is expected to slowly move Westward throughout the week into the Western Gulf as the upper ridge shifts SW into Mexico. Scattered showers and thunderstorms continue to increase across the Western Caribbean Sea as the monsoonal trough continues to slowly lift N. A very broad area of lower pressures encompass the NW Caribbean Sea across the Yucatan Peninsula into the Gulf of Tehuantepec associated with a monsoonal gyre. The overnight guidance continues to advertise this very deep tropical moisture will surge N into the Western Gulf along a shear axis between a building upper ridge to our East and a trough of of low pressure to our West by this weekend. This pressure differential between the features to our East and West should allow for tropical showers and storms to increase along the Middle and Upper Texas Coast into Louisiana this weekend. The morning Weather Prediction Center surface charts suggest a trough just offshore of the Texas Coast extending into Coastal Louisiana. This synoptic pattern remains rather complicated and expect the various computer schemes to struggle resolving the various features as well as any meso features that cannot be determined more than 6 to 12 hours in advance.

Isolated showers and storms should begin to increase the rest of the work week and increase further this weekend in areal coverage as PW's rise above the 2.2+ inch mark suggesting the possibility of very heavy rainfall rates where the tropical like thunderstorms develop. It is not out of the question that some areas where thunderstorms do occur could see 2 to possibly 4 inch rainfall per hour rates raising the potential for very heavy rainfall.

[srainhoutx]

Total precipitation via the 12Z GFS through Monday morning suggests some coastal locations along the Middle/Upper Texas and Louisiana Coastal Counties may approach 6 to 8 inches of rainfall.

[srainhoutx]

The Weather Predication Center afternoon update regarding the expected Surface Charts as well as the Quantitative Precipitation Forecast for the next 7 days.

[Paul Robison]

Dear Brooks Garner:

I would be interested in what you can tell me what you mentioned on Facebook:

A small but strong thunderstorm is hitting the west side of the bay. Another may be forming near downtown

Has it caused any problems? Anyone hurt? What was the wind strength? How many w/out power?

[Katdaddy]

An isolated heavy tropical downpour Paul. Nothing major. Picked up .81" of rain in 15 minutes.

[Paul Robison]

An isolated heavy tropical downpour Paul. Nothing major. Picked up .81" of rain in 15 minutes.

Thanks, katdaddy. I only asked because he described it as "small but strong." My AM radio picked up a good deal of static, which led me to believe that there was some serious lightning production going on.

Anyway, keep up the good work.

[srainhoutx]

The overnight guidance continues to advertise increasing showers and thunderstorms the remainder of the work week with higher chances Saturday and Sunday.

The upper ridge that has brought our extended dry weather continues to shift West as a trough across the Eastern United States digs S across Louisiana into the Gulf of Mexico. The guidance continues to suggest a shear axis developing across the Western Gulf as increasing deep tropical moisture streams N from the Western Caribbean towards Coastal Texas and Louisiana on Friday into the weekend. PW's surge above 2 inches suggesting the potential for heavy tropical rainfall mainly along and S of the 59 Corridor and along the I-10 Corridor in far SE Texas and Louisiana during the weekend. Areas further N should see lesser amounts of rainfall, but will not be totally dry. There is some potential for thunderstorms developing across the Southern Plains and dropping S in the mean upper flow, but the primary concern will be from showers and storms moving N toward the Coast from the surging tropical moisture. The computer models diverge early next week with the GFS suggesting an unsettled pattern continuing Monday through Wednesday while the European suggests high pressure ridges West from the Eastern Gulf and begins the drying process across the Region. Rainfall totals expected during this 'wetter' pattern is expected to range from 1/2 inch with higher totals of 2 to 4 inches with some isolated totals approaching 5 to 7 inches where heavier thunderstorms develop and move slowly. The rainfall threat is expected to slowly decrease early next week with more isolated afternoon showers and a few storms developing. It appears a dryer pattern takes hold later next week as a SE Ridge becomes established and dryer air arrives from the Eastern Pacific as an upper ridge builds across Mexico.

[srainhoutx]

Morning update from the Weather Prediction Center for the Extended Range Forecast.

EXTENDED FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
1159 AM EDT WED JUN 10 2015

VALID 12Z SAT JUN 13 2015 - 12Z WED JUN 17 2015

*** HEAVY RAINFALL POSSIBLE ALONG THE NORTH/NORTHWEST GULF COAST
AND ACROSS PORTIONS OF THE MIDDLE MISSISSIPPI VALLEY AND SOUTHERN
PLAINS ***

...PATTERN OVERVIEW...

ANOMALOUS RIDGING BUILDING IN OVER ALASKA THIS WEEKEND WILL FAVOR
DOWNSTREAM TROUGHING OVER SOUTHWEST CANADA AND THE PACIFIC
NORTHWEST...WITH A POSSIBLE UPPER LOW CLOSING OFF OVER THE BRITISH
COLUMBIA COAST BY EARLY NEXT WEEK. SURFACE BOUNDARIES AT THE
LEADING EDGE OF HEIGHT FALLS IN THE NORTHWEST WILL HAVE AN
INCREASINGLY HARD TIME PUSHING SOUTH AND EAST AND SHOULD
EVENTUALLY STALL OVER THE GREAT LAKES AND NORTHERN MID-ATLANTIC
STATES AS AN UPPER RIDGE EXPANDS OVER THE SOUTHEAST/SOUTH CENTRAL
U.S..

...MODEL EVALUATION AND PREFERENCES...

MODELS ARE IN GOOD LARGE SCALE AGREEMENT WITH THE FLOW OVER THE
CONUS THIS WEEKEND AND INTO EARLY NEXT WEEK. THERE ARE STILL SOME
IMPORTANT SMALLER SCALE DIFFERENCES THAT NEED TO BE
RESOLVED...WHICH INCLUDE THE EXACT TIMING OF A COLD FRONT CROSSING
THE NORTH CENTRAL U.S...THE DETAILS OF POSSIBLE SURFACE LOWS
DEVELOPING ON A WAVY FRONTAL BOUNDARY STRETCHED FROM THE CENTRAL
PLAINS TO THE MID-ATLANTIC COAST...AND JUST HOW FAR WEST THE UPPER
RIDGE EXPANDS OVER THE SOUTH CENTRAL U.S..

GERHARDT

[srainhoutx]

The 12Z GFS suggests some rather impressive rainfall totals through next Thursday morning, if that computer model is correct. Daily shower and some heavy thunderstorms are indicated by the GFS Friday, Saturday, Sunday, Monday into Tuesday as well as Wednesday. The upper ridge to the East develops as well as another to the West, but the GFS suggests a weakness between the ridges will allow daily showers and storms to continue as deep tropical moisture is funneled from the Western Caribbean Sea into the Western Gulf with the Middle/Upper Texas and Louisiana Coasts seeing several rounds of very heavy rainfall.

[srainhoutx]

The Weather Prediction Center afternoon updated surface charts for Days 3 to 7 suggest a trough (indicated by the orange line) draped along the Texas Coast Sunday into early Tuesday.

[wxman57]

My forecast is for a low in the upper 50s and high in the upper 60s on Saturday - for Chicago. That's where I'll be this weekend (attending a wedding). Better bring a coat...

[srainhoutx]

While wxman57 is freezing his tail off in Chicago, we'll be warm and wet down here...

[wxman57]

Increasingly deep and strong flow off the Gulf starting over the weekend and continuing next week should mean increasing moisture and increasing rain chances here.

[jasons2k]

I've been commuting to San Francisco a lot and I'm here (SFO) this week. My coworkers are telling me this is the first time it's actually rained this year.

It was also unusually warm (hot inland) on Monday. It was 20 degrees cooler yesterday. I think that's the first time I've experienced a 20-degree drop in high temperatures without a cold front. Crazy.

By the way, SFO is a wonderful place to visit, but I could never live here. Can't wait to fly home Thursday night - just in time for the fun.

[srainhoutx]

Afternoon updated Quantitative Precipitation Forecast for the next 7 days.

[jasons2k]

That's one heckuva gradient.

[Paul Robison]

The overnight guidance continues to advertise increasing showers and thunderstorms the remainder of the work week with higher chances Saturday and Sunday.

The upper ridge that has brought our extended dry weather continues to shift West as a trough across the Eastern United States digs S across Louisiana into the Gulf of Mexico. The guidance continues to suggest a shear axis developing across the Western Gulf as increasing deep tropical moisture streams N from the Western Caribbean towards Coastal Texas and Louisiana on Friday into the weekend. PW's surge above 2 inches suggesting the potential for heavy tropical rainfall mainly along and S of the 59 Corridor and along the I-10 Corridor in far SE Texas and Louisiana during the weekend. Areas further N should see lesser amounts of rainfall, but will not be totally dry. There is some potential for thunderstorms developing across the Southern Plains and dropping S in the mean upper flow, but the primary concern will be from showers and storms moving N toward the Coast from the surging tropical moisture. The computer models diverge early next week with the GFS suggesting an unsettled pattern continuing Monday through Wednesday while the European suggests high pressure ridges West from the Eastern Gulf and begins the drying process across the Region. Rainfall totals expected during this 'wetter' pattern is expected to range from 1/2 inch with higher totals of 2 to 4 inches with some isolated totals approaching 5 to 7 inches where heavier thunderstorms develop and move slowly. The rainfall threat is expected to slowly decrease early next week with more isolated afternoon showers and a few storms developing. It appears a dryer pattern takes hold later next week as a SE Ridge becomes established and dryer air arrives from the Eastern Pacific as an upper ridge builds across Mexico.

2 questions:
1. Will locations closer to the coast (Galveston, Beaumont, et. al) see these tropical showers and storms?
2. Am I safer here in SW Houston than I would be in, say, League City or Rollover Pass, or do you expect a problematical citywide deluge like we had on Memorial Day?