OPEN CLASS NATIONALS /Pre-World Gliding Championships

UVALDE, TX; USAContest Day 5: Wednesday, August 10, 2011

World Class Soaring!Fly Safe ... and Enjoy!

Uvalde Sky: SSE Aspect1800 CDT; Tuesday Afternoon

Del Rio:By Tuesday Afternoon

CCL higher than InversionBut Mid-level Moisture Increasing

South Texas at 1830 CDT

-Sea Breeze Diffuse-Note NE Mexico Convection

500 mb Wednesday Afternoon Forecast

High Pressure Aloft

H

Infrared Satellite

Water Vapor Satellite

Monday Morning

T

This Morning

Ceilings SimilarSlightly More Coverage

Visible Satellite – This Morning

SE Aspect: UvaldeWednesday Morning

850 mbModel Temp/Moisture

- 30 deg C Area Expanding- Sub-Tropical Moisture West More Extensive

Thunderstorm Outlook(To Right of Lines)

IncreasingThunderstormThreat Area

To Southwest

Surface Plot – 12Z

Pressure Gradient:2.3 mb(+/-0.0)

Pressure Gradient:1.7 mb(-0.4)

Pressure Gradient:2.5(-0.4)

Del Rio Raob

Del Rio Raob24-Hr Comparison

Uvalde RASP Forecast Sounding

Increased Mid-Level Moisture

Corpus Christi Raob

Corpus Christi Raob24-Hour Comparison

BrownsvilleRaob

Forecast Del Rio Sounding (5 PM CDT)

Slightly Higher Inversion HeightMid-Level Moisture Increasing

T/DP Trends

Soaring Graphics

Note: Altitudes are AGL Uvalde

Lift Rates –BLIPMAP

Afternoon 21z(4 PM CDT)

Lift Rates Slightly Up

BoundaryLayer Top

Afternoon 21z(4 PM CDT)

Inversion Slightly Higher

Soaring Forecast

• Delta-T 850-500: 28(+0.5C)

• 850mb Temp: 23.5C(+0.5)

• K-Index, DRT: 34(+1)

• Launch Clouds: SCT-BKN 5000 Feet MSL

• Task: SCT055 to FEW065…then FEW075 late afternoon

• Maximum Temp 39.5C/103F .. (No Change but delayed)

• Lift Rates: 500-600 FPM (+100 fpm)

• Alt Max/Time: 7,500 Ft (FEW Cu) / 1700 CDT

• Trigger/Time: 35C(95F); 1330 CDT

• Winds: SE 8-15Kt (+/-0)

Wednesday Aug 10 2011- More extensive stratus coverage over the Gulf Coast Plain reflecting closer

to that more “normal” for Uvalde. 24-Hr comparisons of Temp/Dewpointshowed similar in Temperatures and slightly higher dew points (and more cloud cover). Note the included picture of the “morning overcast stratus” at Uvalde. Lower level dew points were up 2-4F and combined with similar temperature readings at or below 8000 feet…contest weather forecast included FEW-SCT cumulus for tasks. Widespread morning low cloudiness gave way to BKN037 at launch of 1315 CDT…by launch end at 1445 CDT clouds were BKN-SCT045. Very hazy conditions with the additional moisture with skies slowly raising to SCT050-060 over the task area during the mid to late afternoon. After 1800 CDT skies become SCT070-075 with active convection moving from the southwest over Del Rio. Convective outflow triggered secondary convection in a line that approached Uvalde by 2000 CDT.

- Time period to run the tasks was limited to the mid to very early evening hours due to the expected late start. Lift rates varied significantly from 3 to 10kts…with “average” reports of 5kts. Pilot skill and experience was demonstrated by their “shifting gears” around the task area as lift conditions varied. The variability of the lift was assisted by cumulus that provided consistent thermal markers. Reports of altitudes reached were 7000 to 7500 feet MSL…primarily around 7000 feet. The convection that fired off early in the evening was not a factor but will again occur for the Uvalde area tomorrow…a called rest day.

Wednesday Afternoon Sky, UvaldeEast Aspect: 1600 CDT

- Afternoon Thunderstorm at 1830CDT over Del Rio- Early Evening Cumulus Field from Cotulla (COT)NNW to Edwards County (ECU) over the Uvalde Task Area

Thunderstorm over Del Rio west of Uvalde(West Aspect 1900 CDT; Wed, Aug 10, 2011)

Outook:Thursday 1 PM CDT

H

700 mbHeight/Moisture

Moisture Increasing Over West Texas

FLIGHT RESTRICTIONS

Temporary Flight RestrictionsWednesday: August 10, 2011

--- No V.I.P.s in Task Area (150mi radius)

--- No other unpublished restrictions (Could be “pop-up” Fire-Fight Restrictions)

OPEN CLASS NATIONALS /Pre-World Gliding Championships

UVALDE, TX; USA

World Class Soaring!Fly Safe ... and Enjoy!