Severe Thunderstorm Warning 14, NWS Denver/Boulder, CO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER CO
330 AM MDT SAT MAY 22 2004

.SHORT TERM...NOT A CLEAR CUT SITUATION TO DEAL WITH THIS MORNING.
MODELS SEEM TO AGREE ON THROWING A CHUNK OF ENERGY FROM THE GREAT
BASIN TROUGH ACROSS OUR AREA TODAY.  THIS MAY BE MANIFESTING ITSELF
AT THIS TIME WITH THE DEVELOPING CLOUDS AND LOWERING PRESSURES SEEN
OVER WESTERN COLORADO AND EASTERN UTAH AT THIS TIME.  LATEST SURFACE
ANALYSIS HAS A CYCLONE IN NORTHWEST KANSAS AT 08Z AND WINDS OVER THE
PLAINS AREAS OF THE CWA HAVE BEEN ALL OVER THE PLACE THE LAST COUPLE
OF HOURS.  THEY ARE WANTING TO ORGANIZE SOMEWHAT AT PRESENT...
FAVORING A NORTHWESTERLY DIRECTION.  THE MODELS KEEP THIS LOW FAIRLY
STATIONARY UNTIL THIS EVENING THEN PUSH IT EAST.  THIS FETCH SHOULD
BRING LOWER DEW POINTS INTO THE PLAINS AREAS TENDING TO LESSEN THE
THREAT OF THUNDERSTORMS.  HOWEVER...THE UPPER SYSTEM AND JET MAY
COUNTER THAT TO SOME EXTENT.  BOTH THE GFS AND ETA HAVE QUITE A BIT
OF PRECIPITATION AROUND AS EARLY AS 18Z NEAR THE WYOMING BORDER BUT
NOT CLEAR THAT THIS IS GOING TO OCCUR.  FURTHERMORE...THE ETA SHOVES
A BLAST OF NORTHERLIES ACROSS THE PLAINS THIS AFTERNOON ...EVIDENTLY
ASSOCIATED WITH THIS PRECIPITATION...BRINGING HIGHER DEW POINTS BACK
INTO THE AREA.  TOUGH TO DECIDE HOW CLOSE TO REALITY THIS IS GOING
TO BE AT THIS EARLY HOUR.  UNFORTUNATELY SUBTLE FEATURES SUCH AS
THESE MAY HOLD THE KEY TO WHAT ACTUALLY HAPPENS REGARDING THE
AFTERNOON AND EVENING CONVECTION.  AM NOT PLANNING ON MAKING TOO
MANY MAJOR CHANGES TO THE GOING FORECAST REGARDING POPS.  DO NEED TO
UP MOUNTAIN HIGH TEMPERATURES QUITE A BIT AS THEY ARE TOO COLD FOR
TODAY.

.LONG TERM DISCUSSION...FOR THE LAST WEEK I HAVE BEEN WATCHING THE
MODELS ADVERTISE A DRIER AIRMASS BEYOND 36 HOURS.  EACH NIGHT THE
SURFACE LOW HAS REMAINED IN THE VICINITY OF EASTERN COLORADO...
DRAWING LOW LEVEL MOISTURE BACK INTO NORTHEASTERN COLORADO TO SET UP
ANOTHER AFTERNOON OF POSSIBLE CONVECTION.  THE MODERATE
SOUTHWESTERLY FLOW ALOFT HAS BEEN UNABLE TO TRULY FLUSH THE LOW
LEVEL MOISTURE OUT OF OUT FORECAST AREA.  AND AGAIN TONIGHT THE
MODELS PERSIST IN TRYING TO DRY OUR AREA OUT IN THE 36-48 HOUR TIME
RANGE.  WILL WE BIT OFF ON THIS SCENARIO.  NOT ENTIRELY.  THE
PERSISTENT SOUTHWESTERLY FLOW ALOFT WILL PROBABLY CONTINUE TO
CONTAIN JUST ENOUGH UPPER DYNAMICS AND INSTABILITY TO CONTINUE
DRIVING AFTERNOON AND EVENING SHOWERS OVER THE MOUNTAIN ZONES.
PREVIOUS FORECASTER ALREADY HAD THESE IN THE GRIDS...SO FAR BE IT
FROM ME TO REMOVE THEM.

ONE CHANGE IN THE FORECAST WILL BE TEMPERATURES ON MONDAY.  THE
LATEST GFS AND ETA SHOW SOME SORT OF FRONTAL SURGE OR COOL OUTFLOW
FROM A SUNDAY EVENING CONVECTIVE EPISODE MOVING INTO EASTERN WYOMING
NORTHEASTERN COLORADO MONDAY AFTERNOON.  MOS GUIDANCE FROM BOTH
MODELS HAS ALSO PICKED UP ON THIS.  HAVE LOWERED HIGH TEMPERATURES
ON MONDAY AFTERNOON AND LOW TEMPERATURES TUESDAY MORNING TO REFLECT
THIS CHANGE IN AIRMASS.  IT IS TOO EARLY TO MAKE OTHER CHANGES IN
SENSIBLE WEATHER...SINCE IT IS DIFFICULT TO TELL HOW STRONG THE
COOLING WILL BE AND WHETHER IT HAS MUCH MOISTURE AND INSTABILITY
WITH IT.  LATER SHIFTS WILL HAVE THE OPPORTUNITY TO DEFINE WHAT WILL
OCCUR ON MONDAY.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...NONE.

&&

ET/DANKERS

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE DENVER CO
1047 AM MDT SAT MAY 22 2004

COZ030>051-231200-
JACKSON COUNTY BELOW 9000 FEET-WEST JACKSON AND WEST GRAND
COUNTIES ABOVE 9000 FEET-GRAND AND SUMMIT COUNTIES BELOW 9000
FEET-SOUTH AND EAST JACKSON/LARIMER/NORTH AND NORTHEAST GRAND/
NORTHWEST BOULDER COUNTIES ABOVE 9000 FEET-SOUTH AND SOUTHEAST
GRAND/WEST CENTRAL AND SOUTHWEST BOULDER/GILPIN/CLEAR CREEK/
SUMMIT/NORTH AND WEST PARK COUNTIES ABOVE 9000 FEET-LARIMER AND
BOULDER COUNTIES BETWEEN 6000 AND 9000 FEET-JEFFERSON AND WEST
DOUGLAS COUNTIES ABOVE 6000 FEET/GILPIN/CLEAR CREEK/NORTHEAST PARK
COUNTIES BELOW 9000 FEET-CENTRAL AND SOUTHEAST PARK COUNTY-LARIMER
COUNTY BELOW 6000 FEET/NORTHWEST WELD COUNTY-BOULDER AND JEFFERSON
COUNTIES BELOW 6000 FEET/WEST BROOMFIELD COUNTY-NORTH DOUGLAS
COUNTY BELOW 6000 FEET/DENVER/WEST ADAMS AND ARAPAHOE COUNTIES/
EAST BROOMFIELD COUNTY-ELBERT/CENTRAL AND EAST DOUGLAS COUNTIES
ABOVE 6000 FEET-NORTHEAST WELD COUNTY-CENTRAL AND SOUTH WELD
COUNTY-MORGAN COUNTY-CENTRAL AND EAST ADAMS AND ARAPAHOE COUNTIES-
NORTH AND NORTHEAST ELBERT COUNTY BELOW 6000 FEET/NORTH LINCOLN
COUNTY-SOUTHEAST ELBERT COUNTY BELOW 6000 FEET/SOUTH LINCOLN
COUNTY-LOGAN COUNTY-WASHINGTON COUNTY-SEDGWICK COUNTY-PHILLIPS
COUNTY-
1047 AM MDT SAT MAY 22 2004

THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTHEAST AND NORTH CENTRAL
COLORADO.

.DAY ONE...TODAY AND TONIGHT

ABUNDANT SURFACE MOISTURE HAS CREPT BACK INTO THE NORTHEASTERN
PLAINS THIS MORNING...MAKING THE ATMOSPHERE MORE CONDUCIVE FOR
AFTERNOON THUNDERSTORM ACTIVITY.  THE THUNDERSTORMS WILL FIRST
DEVELOP OVER THE FOOTHILLS THIS MORNING AND WILL MIGRATE EASTWARD
INTO THE PLAINS BY EARLY AFTERNOON.  AN UPPER LEVEL DISTURBANCE
ALONG WITH NEARBY JET ENERGY WILL HELP FURTHER SPAWN THUNDERSTORM
ACTIVITY THIS AFTERNOON.  THERE IS A THREAT OF SEVERE STORMS EAST OF
I-25 AFTER 1 PM WITH THE PRIMARY THREAT BEING LARGE HAIL.  THE AREA
WITH THE BEST CHANCE OF SEEING SEVERE WEATHER WILL ROUGHLY BE IN A
LINE FROM FORT LUPTON EXTENDING NORTHEASTWARD ALONG I-76.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY

THERE IS JUST A SLIGHT RISK OF THUNDERSTORMS FROM TIME TO TIME NEXT
WEEK.  THE THREAT OF ANY SEVERE WEATHER IS LOW.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE REQUIRED AFTER 1 PM.