Severe Thunderstorm Warning 24, NWS Denver/Boulder, CO

NORTHEAST AND NORTH CENTRAL COLORADO AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER COLORADO
330 AM MDT WED MAY 17 2000

CLASSIC CYCLOGENESIS TAKING PLACE OVR NERN CO TODAY.  ONE DISTINCT
JET MAX IS MOVING AROUND THE EAST SIDE OF THE UPPER TROUGH AND IS
PRODUCING WHOPPING LIFT OVER GENERALLY DRY AIR ACROSS WRN CO/WY.
ANOTHER SPEED MAX ON THE BACK SIDE IS KEEPING THE TROUGH FROM MOVING
EAST TOO QUICKLY.  THE NGM DOES NOT APPEAR TO CAPTURE THIS STRUCTURE
WELL...THE ETA/AVN ARE BETTER.  RESULT OF THIS STRUCTURE IS
DEEPENING OF THE SURFACE LOW OVER NERN CO TODAY...WHILE NOT MOVING
IT EAST TOO QUICKLY SINCE THE WINDS ALOFT WILL STILL BE PRETTY SLY.
SUBSTANTIAL COOLING ALOFT SHOULD ALREADY BE UNDERWAY...ETA SHOWS 500
TEMP DROPPING TO -16C BY 12Z.  AT THE SURFACE OUTFLOW FROM NEB
PANHANDLE STORMS IS COMBINING WITH THE DEVELOPING SURFACE LOW.  AT
09Z THE BOUNDARY RUNS FROM DEN THROUGH AKO WHERE IT INTERSECTS THE
DRYLINE.  MILD AND MOIST LOW LEVEL AIR IS WRAPPING BACK AROUND THE
LOW INTO AREAS N OF DENVER...WHILE THE AIR SOUTH OF DENVER IS BONE
DRY.  THE 00Z AND 06Z ETA BOTH DROPPED THIS BOUNDARY SOUTH WITH THE
LOW ULTIMATELY DEEPENING CLOSER TO LIC.  NOT SURE ABOUT THAT LEVEL
OF DETAIL...BUT THE GENERAL PATTERN LOOKS GOOD.

EVEN WITHOUT MUCH HEATING THIS MORNING...RAPID DESTABILIZATION WILL
OCCUR AS THE COOLING ALOFT DISSIPATES THE CAP OVER THE MOIST AIR.
SURFACE BASED CAPES ARE 1800 J/KG NOW AS FAR WEST AS FORT COLLINS.
STRONG DYNAMIC FORCING WILL BE MOVING ONTO THE PLAINS AS WELL.  AS A
RESULT...THUNDERSTORMS SHOULD FORM ON THE NORTH SIDE OF THE BOUNDARY
THIS MORNING.  THE WIND FIELD LOOKS VERY FAVORABLE FOR SEVERE
HAIL...WITH THE GREATEST THREAT IN A BAND EAST-NORTHEAST FROM
DENVER.  HOPEFULLY SOME EASTWARD PROGRESSION IS NEEDED BEFORE THE
INGREDIENTS ARE GOOD ENOUGH...BUT BIG STORMS COULD START CLOSE TO
DEN THIS MORNING.  MORE WIDESPREAD CONVECTION SHOULD BREAK OUT
FARTHER NORTH AND WEST...AND TRANSITION TO STRATIFORM RAIN BY THE
END OF THE DAY.

FOR THE REST OF THE PACKAGE...STRONG N WINDS AS THE LOW CRAWLS EAST
TONIGHT.  MODEL WINDS ARE NOT STRONG ENOUGH TO JUSTIFY A HIGH WIND
WATCH...BUT COULD BE CLOSE.  SHOULD BE A WIDESPREAD SIGNIFICANT RAIN
FOR NERN CO...AND SNOW LEVEL LOWERS TO AROUND 6000 FEET BY MORNING.
THE MOUNTAINS APPEAR TO BE ON THE EDGE OF THE SERIOUS LIFT AND WINDS
WILL NOT BE AS STRONG...SO NO SNOW HIGHLIGHT YET EITHER...THOUGH 6
OR 8 INCHES IN THE FAVORED LOCATIONS SEEMS LIKE A GOOD POSSIBILITY.
ON THU THE ATMOSPHERE IS QUITE STABLE...AND ISENTROPIC LIFT SHOULD
BE MOVING OUT DURING THE DAY.  CLEARING THU NIGHT COULD BRING
ANOTHER FREEZE THREAT...BUT THERE WILL PROBABLY BE ENOUGH LOW LEVEL
MOISTURE TO PREVENT ANOTHER WIDESPREAD FREEZE.  AVN SHORTWAVE FOR
FRI IS MUCH WEAKER IN THE LATEST ETA AND WE SHOULD BE VERY STABLE...
SO I WILL REMOVE THE POPS.  SAT/SUN FORECAST SEEMS OK.
GIMMESTAD

.DEN...NONE.