Lightning Strike in Colorado, October 9, 2001

WESTERN COLORADO & EASTERN UTAH AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
300 AM MDT TUE OCT 9 2001

INTERACTION OF SHEARING TROUGH OVER THE FOUR CORNERS AREA AND GOOD
AGEOSTROPHIC FLOW IN THE RIGHT ENTRANCE REGION OF WYOMING JET HAS
CAUSED NUMEROUS SHOWERS OVER NORTHWEST COLORADO.  EARLIER MODEL RUNS
SEEMED TO UNDERDO PRECIPITABLE WATER AMOUNTS.. BUT SEEM TO BE PLAYING
CATCH UP FOR THE 00Z RUNS.  STRONGER SHORT WAVE OVER NORTHERN NEVADA
HAS A LITTLE MORE AMPLITUDE AND A FEW HOURS SLOWER THAN YESTERDAY/S
MODEL RUNS SHOWED.  THE NET RESULT WILL BE MORE SHOWERS TODAY THAT
WILL PERSIST LONGER THAN PREVIOUSLY ANTICIPATED.  COLD ADVECTION IN
THE MID LEVELS WILL KEEP THE MOIST AIR MASS UNSTABLE THROUGH THE
AFTERNOON.  COLD FRONTAL PASSAGE ACROSS THE NORTHERN ZONES OCCUR
AROUND EARLY AFTERNOON.. AND PRECIPITABLE WATER GRADUALLY DECREASES
WITH TIME.  BUT NORTHWEST FLOW NOT PARTICULARLY STRONG.. THEREFORE
MOISTURE WILL LINGER IN THE LOWER LEVELS TO KEEP SCATTERED SHOWERS
LASTING INTO THE EVENING.  SUFFICIENT COLD AIR TO LOWER SNOW LEVELS
TO THE VALLEY FLOORS ACROSS THE HIGHER NORTH AND CENTRAL VALLEYS.
EXPECT LOCAL VALLEY ACCUMULATIONS BUT MAINLY ON GRASSY SURFACES. MORE
SNOW ANTICIPATED IN THE HIGH COUNTRY.. BUT BEST UPWARDS FORCING AND
MOISTURE WILL BE EAST OF THE AREA BY THE TIME COLDER AIR ARRIVES TO
LOWER SNOW LEVELS.  BELIEVE SNOW AMOUNTS WILL BE GENERALLY LESS THAN
4 INCHES.. AND SEE NO NEED FOR ANY ADVISORIES AT THIS TIME.  FOR THE
SOUTHERN ZONES.. LESS SHOWER ACTIVITY EXPECTED DUE TO LESS THAN
IDEAL OROGRAPHIC FLOW AND FARTHER FROM UPPER AIR SUPPORT.

LIMITED MOISTURE WITH SECONDARY IMPULSE ON WEDNESDAY.. BUT LIGHT
NORTHWEST FLOW MAY INDUCE OROGRAPHIC LIGHT SHOWERS OVER NORTHWEST
COLORADO.  OTHERWISE MOSTLY SUNNY CONDITIONS FOR VALLEY LOCATIONS
AS AIR MASS WILL BE QUITE DRY.

FRISBIE

WESTERN COLORADO AND EASTERN UTAH EMERGENCY MANAGERS SHOULD MAINTAIN
A NORMAL LEVEL OF WEATHER AWARENESS TODAY.

.GJT...NONE.