Hail and Damaging Winds in Colorado, August 10, 2005

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GOODLAND KS
0220 PM MDT WED AUG 10 2005

.DISCUSSION...MAIN FORECAST PROBLEMS WILL FOCUS ON PRECIPITATION
CHANCES AND THEN HIGH TEMPERATURES AS A TRICKY FORECAST UNFOLDS WITH
QUASI-STATIONARY BOUNDARY DRIFTING AROUND...INTERACTING WITH WEAK
SHORTWAVE TROUGH ENERGY IN AN INCREASINGLY ACTIVE PATTERN.

500 MB PATTERN SHOWING A BROAD FLAT RIDGE ACROSS THE SOUTHERN HALF
OF THE CONUS. RIDGE IS MOST PRONOUNCED OVER SOUTHWEST
COLORADO...NICELY MATCHING WITH CURRENT WATER VAPOR IMAGERY. GENERAL
EVOLUTION OF MID LEVEL FEATURES IN REASONABLY GOOD AGREEMENT AMONGST
FORECAST MODELS. ALL SHOW A WEAKENING AND SOUTHWARD SUPPRESSION OF
THE 500 MB RIDGE BEGINNING TONIGHT AND CONTINUING TOMORROW WITH SLOW
HEIGHT FALLS OVER THE AREA. FLOW STARTS TO BECOME VERY AMPLIFIED
WITH A REX BLOCK OVER EASTERN PACIFIC...AND HUDSON BAY LOW
DEEPENING. SOUTHWARD SUPPRESSION OF FLAT CONUS RIDGE APPEARS TO BE
IN RESPONSE TO SHORTWAVE TROUGH DESCENDING SOUTHWARD INTO THE CREST
OF RIDGE. BY SATURDAY...FLOW IS VERY AMPLIFIED WITH A BERMUDA HIGH
TO THE EAST AND PACIFIC BLOCK TRANSITIONING INTO A MORE OMEGA
LOOKING SHAPE...AND A HUDSON BAY LOW BECOMING QUITE DEEP.

SURFACE REFLECTION OF THIS PATTERN WILL SHOW A HIGH DESCENDING
SOUTHWARD FROM WESTERN CANADA BY FRIDAY. SURFACE FRONT WILL SLIP
SOUTH OF THE AREA...PROVIDING FOR AN UPSLOPE SITUATION TO DEVELOP.
COORDINATION WITH SURROUNDING OFFICES REACHED AN AGREEMENT ON A
SHARP CUTTING OF MAX TEMPERATURES ON SATURDAY TO LEVELS WELL BELOW
NORMAL.

FOR PRECIPITATION...FIRST THREE DAYS LOOK VERY ACTIVE WITH THE
SURFACE FRONT CONTINUING TO ACT AS A FOCUS FOR THUNDERSTORMS. SEVERE
THREAT POSSIBLE ON FRIDAY WITH INSTABILITY AND SHEAR MAXIMIZED ACROSS
SOUTHERN NEBRASKA ZONES. DAY 3 OUTLOOK FROM SPC SHOWS A SLIGHT RISK
IN THIS SAME REGION...WHICH LOOKS REASONABLE.

EXTENDED (SUNDAY THROUGH WEDNESDAY)...

SURFACE HIGH SHOULD SETTLE SOUTHWARD ON SUNDAY WITH CONTINUED
UPSLOPE FLOW. EARLIER MENTIONED SHORTWAVE TROUGH AND ASSOCIATED VORT
MAXES TO ROTATE THROUGH AREA...CONTINUING AT LEAST SLIGHT CHANCES OF
RAINFALL THROUGH MUCH OF THE EXTENDED PERIOD. GFS EXPLODING QPF
BOMBS OFF AND ON OVER SEVERAL PERIODS. FOR THE TIME BEING...DID NOT
TRY TO PINPOINT THESE EVENTS OTHER THAN A RATHER GENERAL ASSIGNMENT
OF POPS.

TEMPERATURE FORECAST WOULD BEGIN WITH MUCH BELOW NORMAL TEMPERATURES
ON SUNDAY WITH HIGH PRESSURE AND EASTERLY WIND CONTINUING. AIRMASS
MODIFICATION WILL BEGIN THEREAFTER...REACHING TO NEAR NORMAL AGAIN
BY TUESDAY AND WEDNESDAY AS SHORTWAVE TROUGH ENTERING THE PACIFIC
NORTHWEST FORCES RIDGING AHEAD OF IT AND PUMPS THE SOUTHERN CONUS
RIDGE BACK UP AGAIN.

&&

.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
NE...NONE.
CO...NONE.
&&

JOHNSON

HAZARDOUS WEATHER OUTLOOK...CORRECTED
NATIONAL WEATHER SERVICE GOODLAND KS
1046 AM MDT WED AUG 10 2005

COZ090>092-KSZ001>004-013>016-027>029-041-042-NEZ079>081-111200-
CHEYENNE KS-CHEYENNE COUNTY CO-DECATUR KS-DUNDY NE-GOVE KS-GRAHAM KS-
GREELEY KS-HITCHCOCK NE-KIT CARSON COUNTY CO-LOGAN KS-NORTON KS-
RAWLINS KS-RED WILLOW NE-SHERIDAN KS-SHERMAN KS-THOMAS KS-WALLACE KS-
WICHITA KS-YUMA COUNTY CO-
1046 AM MDT WED AUG 10 2005

THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTHWEST KANSAS...EXTREME
SOUTHWEST NEBRASKA...AND EAST CENTRAL COLORADO.

.DAY ONE...TODAY AND TONIGHT

A WEAK WARM FRONT WILL LIFT NORTH ACROSS THE TRI STATE AREA THIS
AFTERNOON AND EVENING...PROVIDING THE FOCUS FOR ANOTHER ROUND OF
THUNDERSTORMS ACROSS THE TRI STATE AREA. ISOLATED THUNDERSTORMS WILL
BE POSSIBLE THROUGH EARLY AFTERNOON...BUT THUNDERSTORMS WILL
INCREASE IN COVERAGE DURING THE AFTERNOON AND EVENING HOURS.

STORMS THAT FORM THIS AFTERNOON WILL HAVE THE POTENTIAL TO BECOME
SEVERE...WITH LARGE HAIL...DAMAGING WIND GUSTS AND HEAVY RAIN BEING
THE MAIN THREAT. THERE IS ALSO AN ISOLATED TORNADO THREAT ALONG THE
WARM FRONT...WHICH WILL BE LOCATED ALONG AND NORTH OF INTERSTATE 70.
THE THREAT FOR SEVERE WEATHER WILL DIMINISH AFTER 9 PM MDT (10 PM
CDT) AS THUNDERSTORMS BECOME ELEVATED AND THE MAIN THREAT WILL
TRANSITION TO HEAVY RAIN AND LIGHTNING.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

SEVERAL DISTURBANCES AND AN APPROACHING COLD FRONT WILL
MAKE THUNDERSTORMS POSSIBLE NEARLY EVERY DAY THROUGH TUESDAY.
AT THIS TIME WIDESPREAD SEVERE WEATHER IS NOT EXPECTED SO THE MAIN
THREAT WILL BE DANGEROUS LIGHTNING.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED AFTER 2 PM MDT (3 PM CDT).

JRM