Severe Thunderstorm Warning 1, NWS Denver/Boulder, CO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER CO
325 PM MDT MON APR 19 2004

.SHORT TERM...RADAR IMAGERY AND SATELLITE IMAGERY SHOWS THAT THE
UPPER LEVEL TROUGH IS MAKING ITS WAY ACROSS UTAH THIS AFTERNOON.
PREVIOUS FORECAST PACKAGE HAD ISOLATED SHOWER COVERAGE OVER THE
MOUNTAINS LATE THIS AFTERNOON INCREASING TO SCATTERED THROUGH THE
EVENING.  HAVE NOT SEEN VERY MUCH LIGHTNING OUT OF THE DEVELOPING
SHOWERS YET...BUT CAN NOT TAKE OUT THE THUNDER YET.  IN FACT...A FEW
STRIKES HAVE BEEN OBSERVED IN NORTHERN UTAH.  THE UPPER PATTERN IS
VERY PROGRESSIVE...SO TONIGHTS UPPER TROUGH SHOULD BE OUT OF THE
STATE BY MORNING.  ANOTHER SHORT WAVE IS ON ITS HEALS AND WILL BE
COMING INTO THE THE STATE TOMORROW EVENING WITH ANOTHER ROUND OF
SHOWERS FOR THE MOUNTAINS.

ON THE PLAINS...LOW LEVEL AIRMASS HAS REMAINED DRY TODAY WITH STRONG
SOUTHERLY WINDS CAUSED BY THE SURFACE HIGH OVER THE PLAINS AND A LEE
TROUGH DEVELOPING NEAR THE EASTERN ROCKY FOOTHILLS.  THE SOUTHERLIES
HAVE NOT TAPPED INTO THE ABUNDANT LOW LEVEL MOISTURE OVER TEXAS
YET.  BUT EXPECT THAT TO CHANGE OVERNIGHT.  HOWEVER...AFTER THE
UPPER TROUGH PASSES TONIGHT...THE LEE TROUGH WILL ALSO EJECT...
ALLOWING DOWNSLOPING WESTERLIES TO SPREAD EASTWARD ACROSS THE
PLAINS.  THE DEEP MOISTURE TOMORROW WILL BE CONFINED TO THE EASTERN
COLORADO BORDER.  FOR THAT REASON...THE ONLY POPS FOR TOMORROW WILL
BE IN THE MOUNTAINS AND ALONG THE EASTERN BORDER.  TEMPERATURES WILL
REMAIN SEASONAL DUE TO THE ZONAL AND PROGRESSIVE NATURE OF THE UPPER
FLOW PATTERN.

.LONG TERM DISCUSSION...TUE NGT-THU...MDLS DIVE PAC NW NEGATVELY
TILTED UPR TROF INTO CNTRL RCKYS BY END OF PERIOD.  AVN IS DEEPER
AND FARTHER S WITH SYS THAN ETA AND PREFER THE DEEPER SOLUTION ATTM
SINCE IT IS MORE IN LINE WITH THE ECMWF.  SCT SNW SHWRS IN MTNS WILL
BCM LIKELY ON WED NGT INTO FRI.  SCT RAIN SHWRS ON PLAINS WED AFTN
WILL CONT THRU THU AFTN AND CHANGE TO SCT RAIN AND SNW SHWRS THU NGT.
IF THE TRACK IS FARTHER S THERE CUD BE SIGNIFICANT SNW OVR PLAINS
ON THU NGT.  TEMPS WILL GRADUALLY COOL THRU THU WHEN SFC CDFNT
SPREADS S OVR PLAINS AND LO LVL UPSLP FLO DVLPS ALG ERN SLPS.
WILL MAKE ONLY SML ADJUSTMENTS TO MOS GFS MOS TEMP GUIDANCE AND
UNDERCUT MOS GUIDANCE ON THU.

IN EXTENDED PERIOD...FRI-MON...UPR TROF WILL LINGER OVR CNTRL RCKYS
ON FRI WITH CONTD CHC OF PCPN ACRS AREA.  SAT WILL BE DRY WITH SHT
WV RDG ACRS AREA.  GFS SHWS WK SHT WV ON SUN IN NWLY FLO ALF...BUT
WILL KEEP AREA DRY FOR NOW.  UPR RDG STARTS TO BUILD OVR CNTRL RCKYS
ON MON.  TEMPS WILL BE COOL ON FRI AND GRADUALLY WARM THRU THE WKND.
WILL MAKE ONLY SML ADJSTMNTS TO MOS TEMP GUIDANCE AT THIS TIME BUT
MAY NEED TO COOL TEMPS BLO GUIDANCE ON FRI TO BE MORE IN LINE WITH
THU TEMPS.

&&

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

KDRBY/GARD...WFO BOULDER

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE DENVER CO
1058 AM MDT MON APR 19 2004

COZ030>051-201200-
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-
1058 AM MDT MON APR 19 2004

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

.DAY ONE...TODAY AND TONIGHT

A WEATHER DISTURBANCE MOVING ACROSS NORTHERN AND CENTRAL COLORADO
LATE THIS AFTERNOON AND TONIGHT MAY PRODUCE SOME THUNDERSTORMS OVER
THE NORTHEAST PLAINS THIS EVENING.  IT APPEARS THE BEST CHANCE OF
THUNDERSTORMS WILL BE NORTH OF A LINE FROM GREELEY TO AKRON DURING
THE EVENING HOURS.  THE STORMS MAY PRODUCE WIND GUSTS TO 50 MPH
ALONG WITH SOME SMALL HAIL AND BRIEF HEAVY RAIN.  SOUTH OF THE
GREELEY-AKRON LINE...THE THREAT OF THUNDERSTORMS IS MINIMAL...BUT
GUSTY SOUTHEAST WINDS OF 15 TO 30 MPH ARE EXPECTED TO CONTINUE
THROUGH THE AFTERNOON AND INTO THE EVENING.  IN THE MOUNTAINS...
SCATTERED SNOW SHOWERS WILL DEVELOP BY LATE AFTERNOON OR EVENING
WITH AN ISOLATED THUNDERSTORM POSSIBLE.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY

ANOTHER WEATHER SYSTEM WILL MOVE ACROSS COLORADO LATE WEDNESDAY
THROUGH FRIDAY.  THIS STORM WILL BRING A BETTER CHANCE OF MEASURABLE
RAINFALL ACROSS THE PLAINS AND ACCUMULATING SNOWFALL TO THE
MOUNTAINS AND EASTERN FOOTHILLS.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL NOT BE NEEDED TODAY OR TONIGHT.

DANKERS/GARD...WFO BOULDER