September 2015: Pleasant Weather To End The Month

[Rip76]

Coming down here in SageGlen.

Windy too.

[Paul Robison]

Coming down here in SageGlen.

Windy too.

I know. 60 mph. Probably higher. And Brooks was worried about Sunday!

[srainhoutx]

The area of disturbed weather currently over the Yucatan Peninsula has been declared INVEST 99L by the National Hurricane Center.

[srainhoutx]

Morning briefing from Jeff:

Upper level low pressure system developing over SE TX will increase rain chances Sunday-Tuesday. Some potential for heavy rainfall over portions of SE TX during this period.

Fairly complicated pattern will unfold along the TX coast over the next 48-72 hours as an upper level low develops and intensifies near the TX coast and a surge of deep tropical moisture/surface low pressure moves northward out of the southern Gulf while at the same time a coastal trough attempts to form along the TX coast. IT shall certainly be interesting to see how the TX coastal trough and the surface low moving toward the NC Gulf coasts react to each other over the next few days. All these features will produce a strong rainfall gradient across SE TX with likely rainfall southeast of a line from Palacios to Houston to Liberty and much lower chances around College Station. Position of the upper level low will be critical in determining where the deepest moisture surges inland over SE TX with current best projections from Freeport to Galveston Bay and eastward into Louisiana. Will have the highest rain chances with the deepest moisture on Sunday and Monday or roughly along and SE of US 59. Tropical moisture will promote higher rainfall rates, so will need to keep an eye on areas of slow storm motions, training, or cell mergers in addition to areas that may be hit a day or two in a row.

Latest wind shear and satellite analysis shows strong upper level winds continue and will likely continue over the Gulf of Mexico as tropical disturbance currently over the Yucatan lifts northward into the Gulf of Mexico and approaches the US Gulf coast by Tuesday/Wednesday. Conditions do not look favorable for a tropical cyclone to develop, but a sub-tropical system is possible with a large wind field and most convection to the ENE and NE any surface center. How this surface low will interact with the TX coastal trough that looks to form late Sunday is unclear. Currently expecting the central Gulf surface low to remain weak enough that NE/N winds on its western flank does not interrupt the coastal trough circulation off the TX coast. How this all works out over the Gulf of Mexico could have some impact on local rain chances.

Tides:
ENE/NE having been ongoing since Thursday and water levels are up some along the Gulf beaches. “Super” moon on Sunday will only increase tides further and we could be near 2.0 ft of total water level rise on the east facing beaches at times of high tide Sunday and Monday. Increasing ESE swell will also pile a little more water on the coast. Looking for tides to stay below 4.0 ft advisory level, but some beach areas could be inundated at high tides Sunday and Monday and could be close to some roads on Bolivar.

[srainhoutx]

Reconnaissance Missions schedule tasked for 99L...if necessary...

Code: Select all

WEATHER RECONNAISSANCE FLIGHTS
CARCAH, NATIONAL HURRICANE CENTER, MIAMI, FL.
1230 PM EDT SAT 26 SEPTEMBER 2015
SUBJECT: TROPICAL CYCLONE PLAN OF THE DAY (TCPOD)
         VALID 27/1100Z TO 28/1100Z SEPTEMBER 2015
         TCPOD NUMBER.....15-123

I.  ATLANTIC REQUIREMENTS
    1. SUSPECT AREA (GULF OF MEXICO)
       FLIGHT ONE -- TEAL 71           FLIGHT TWO - TEAL 72
       A. 27/2100Z                     A. 28/1130Z, 1730Z
       B. AFXXX 01EEA INVEST           B. AFXXX 0211A CYCLONE
       C. 27/1900Z                     C. 28/1000Z
       D. 22.5N 89.5W                  D. 26.0N 88.0W
       E. 27/2030Z TO 27/2330Z         E. 28/1100Z TO 28/1730Z
       F. SFC TO 10,000FT              F. SFC TO 10,000FT

    2. OUTLOOK FOR SUCCEEDING DAY.....CONTINUE 6-HRLY FIXES
    IF SYSTEM DEVELOPS AND REMAINS A THREAT.

[Katdaddy]

A small tropical funnel in Pearland today while visiting mom.

[unome]

http://www.wpc.ncep.noaa.gov/metwatch/m ... 20&yr=2015



MESOSCALE PRECIPITATION DISCUSSION 0520
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
641 AM EDT SUN SEP 27 2015

AREAS AFFECTED...PORTIONS OF THE UPPER/MIDDLE TX COAST

CONCERNING...HEAVY RAINFALL...FLASH FLOODING POSSIBLE

VALID 271040Z - 271540Z

SUMMARY...A TRAINING BAND OF CONVECTION IS BRUSHING THE COAST NEAR
GALVESTON ISLAND WITH RAIN RATES OF 1.5" AN HOUR. CONSIDERING THE
URBAN ENVIRONMENT AND FAVORABLE PARAMETERS, FLASH FLOODING IS
POSSIBLE OVER THE NEXT FIVE HOURS.

DISCUSSION...A LOW- TO MID-LEVEL DISTURBANCE OVER THE NORTHWEST
GULF OF MEXICO HAS LED TO A FEEDER BAND SCRAPING THE TX COAST FROM
JUST SOUTH OF HIGH ISLAND INTO GALVESTON ISLAND EXTENDING
SOUTHWEST TOWARDS FREEPORT. UPPER DIVERGENCE IS SEEN WITH THIS
BAND ON RECENT SATELLITE IMAGERY. MUCAPES ARE 500-1000 J/KG IN
THIS REGION, INFLOW AT 850 HPA IS 20-30 KTS (CLOSE TO DOUBLE THE
MEAN 850-400 HPA WIND), PRECIPITABLE WATER VALUES ARE 1.6-1.8",
AND A BOUNDARY JUST OFF THE COAST IS BEING REINFORCED BY A LAND
BREEZE.

RADAR ESTIMATES SHOW HOURLY RAIN RATES UP TO 1.5" WITHIN THIS
BAND, WHICH WOULD COMPROMISE URBAN AREAS. WITH THE FLOW OFF THE
WARM GULF OF MEXICO, INSTABILITY SHOULD REMAIN IN PLACE. RAP
GUIDANCE INDICATES THAT 850 HPA INFLOW SHOULD BE LESSENING LATER
THIS MORNING, WHICH SHOULD ALLEVIATE THE CURRENT HEAVY RAIN
THREAT. THE CAM GUIDANCE SHOWS SPREAD IN THIS REGION, WITH THE
00Z SPC WRF, 00Z 3 KM NAM, AND 00Z WRF4NSSL HAVING SOME CONCEPT OF
WHAT IS ONGOING. WITH THE LOW- TO MID-LEVEL DISTURBANCE PUSHING
NORTHWARD, THERE IS A CHANCE THE BAND COULD PUSH SLIGHTLY INLAND
AND PIVOT DURING THE NEXT SEVERAL HOURS, WHICH COULD ENHANCE RAIN
RATES BETWEEN HOUSTON AND PORT ARTHUR TX. HOWEVER, WITH LIMITED
INSTABILITY INLAND, HEAVY RAIN SHOULD NOT GET TOO FAR INLAND.
CONSIDERING AVAILABLE MOISTURE, HOURLY RAIN RATES UP TO 2" ARE
POSSIBLE. USING THE 3 KM NAM AS A GUIDE, AND PER RECENT RADAR
TRENDS, LOCAL AMOUNTS UP TO 3-5" ARE POSSIBLE, WHICH WOULD CAUSE
ISSUES IN URBAN AREAS.

ROTH

ATTN...WFO...HGX...LCH...

ATTN...RFC...LMRFC...WGRFC...

LAT...LON 29849391 29669376 29619405 29519439 28979517
28439614 28539632 29029616 29519564 29839477

[Katdaddy]

Lots of rain along the Upper TX Coast thanks to an upper level low. This upper level low will keep the shear high and will not allow Invest 99L to strengthen much in the Central GOM. Steady light rain here in League City with only .08" but more needed rain on the way.

[unome]

current WPC Met Watch: http://www.wpc.ncep.noaa.gov/metwatch/metwatch_mpd.php

WPC short-range discussion: http://www.wpc.ncep.noaa.gov/discussion ... isc=pmdspd
The Gulf Coast from Texas to Florida will have showers and thunderstorms as a couple of areas of low pressure develop over the Gulf of Mexico. The exact position of these surface lows remain uncertain, but the lows will promote showers in coastal areas of Texas, Louisiana, Mississippi, Alabama, and Florida. Locally heavy downpours are possible.

high res surface analysis: http://www.wpc.ncep.noaa.gov/html/sfc-zoom.php

from: http://earth.nullschool.net/about.html

surface http://earth.nullschool.net/#current/wi ... 24.53,2837

850 hPa http://earth.nullschool.net/#current/wi ... 24.53,2837

700 http://earth.nullschool.net/#current/wi ... 24.53,2837

500 http://earth.nullschool.net/#current/wi ... 24.53,2837

[srainhoutx]

A weak surface low has developed about 150 miles SE of Galveston as is rotating NW around the upper low located inland near Corpus Christi. Coastal showers and embedded thunderstorms should continue throughout the day into tomorrow mainly S of HWY 105. Unfortunately for those that had hoped to view the Red Moon eclipse, cloud cover is likely not to be cooperative across SE Texas this evening.

[mckinne63]

Not much here in Stafford. It is just cloudy and gloomy, with some drizzle mixed in. Can we expect some real rain to develop?

[Ptarmigan]

Would be nice if the sky cleared up for the total lunar eclipse.

[BlueJay]

Would be nice if the sky cleared up for the total lunar eclipse.

I second that emotion!!!

What phenomenon is it that allows cloud cover during this unique total lunar eclipse so that we are not able to view it? Scientific or just coincidence?

[ticka1]

latest fron jeff lindner:

A non-tropical surface low has formed this afternoon roughly 125 miles SE of Galveston Island and has anchored an persistent area of excessive rainfall south of Sabine Pass where radars rom both Houston and Lake Charles indicate as much as 10-12 inches has fallen today. This surface low is entangled within an upper level low located near the TX coast bend and is expected to drift NW tonight into early Monday and could move inland near Galveston Is/Bay. Will need to watch for the potential for excessive rainfall near/just to the northeast of the core of the surface circulation as has been seen today offshore of Sabine Pass, TX. Rainfall amounts of 1-2 inches will be likely near the coast possibly as far inland as US 59 through Tuesday, but as seen today isolated locations could see much higher totals under slow moving convection.

There will likely be a very sharp rainfall gradient across the region on Monday similar to today with areas closet to the coast seeing the most rainfall and areas further inland seeing less.

Tides:
Tides are running 1-2 feet above normal currently due to upcoming “super” moon…in perigee…this evening. Surface winds at Galveston have turned to the north and increased into the 20-35mph range this afternoon on the west side of the surface low, but the larger scale flow across the northern Gulf is generally E to W which is resulting in both wave run-up and tidal pile-up on the upper TX coast. So far no big issues today, but highest tides will be tonight and Monday. A Nippion Oil Platform just east of the center is currently reporting a sustained east wind of 36 kts (41mph) and the buoy 20 E of Galveston is gusting to 29 kts (33mph).

[Ptarmigan]

latest fron jeff lindner:

A non-tropical surface low has formed this afternoon roughly 125 miles SE of Galveston Island and has anchored an persistent area of excessive rainfall south of Sabine Pass where radars rom both Houston and Lake Charles indicate as much as 10-12 inches has fallen today. This surface low is entangled within an upper level low located near the TX coast bend and is expected to drift NW tonight into early Monday and could move inland near Galveston Is/Bay. Will need to watch for the potential for excessive rainfall near/just to the northeast of the core of the surface circulation as has been seen today offshore of Sabine Pass, TX. Rainfall amounts of 1-2 inches will be likely near the coast possibly as far inland as US 59 through Tuesday, but as seen today isolated locations could see much higher totals under slow moving convection.

There will likely be a very sharp rainfall gradient across the region on Monday similar to today with areas closet to the coast seeing the most rainfall and areas further inland seeing less.

Tides:
Tides are running 1-2 feet above normal currently due to upcoming “super” moon…in perigee…this evening. Surface winds at Galveston have turned to the north and increased into the 20-35mph range this afternoon on the west side of the surface low, but the larger scale flow across the northern Gulf is generally E to W which is resulting in both wave run-up and tidal pile-up on the upper TX coast. So far no big issues today, but highest tides will be tonight and Monday. A Nippion Oil Platform just east of the center is currently reporting a sustained east wind of 36 kts (41mph) and the buoy 20 E of Galveston is gusting to 29 kts (33mph).

The surface low has ruined our chance of seeing the total lunar eclipse. Send it to somewhere else.

[DoctorMu]

Showers inward this am as ULL drifts NW. CLL seeing a couple of mini-bands.

[Texaspirate11]

On and off rain today in the Bay area. Not much action.

[Rip76]

This looks awesome.

http://wwwghcc.msfc.nasa.gov/cgi-bin/ge ... mframes=20

[kayci]

This looks awesome.

http://wwwghcc.msfc.nasa.gov/cgi-bin/ge ... mframes=20