FNUS75 KPUB 290513
FWSPUB

SPOT FORECAST FOR SAND GULCH...EL PASO
NATIONAL WEATHER SERVICE PUEBLO CO
1113 PM MDT THU APR 28 2011

IF CONDITIONS BECOME UNREPRESENTATIVE...CONTACT THE NATIONAL WEATHER
SERVICE.

...HIGH WIND WARNING IN EFFECT FROM 6 AM TO 6 PM MDT FRIDAY...

.DISCUSSION...

A POWERFUL JET STREAM WILL TRACK ACROSS COLORADO ON FRIDAY...
BRINGING HIGH WINDS AND LOW HUMIDITIES TO THE BURN SITE.  STRONG
DOWNSLOPE WINDS GUSTING TO 60 MPH...AND POSSIBLY AS HIGH AS 80
MPH...WILL SWEEP ACROSS THE BURN SITE TOMORROW MORNING...AND
LAST THROUGHOUT THE DAY.  THE STRONG DRYING EFFECT OF THE
DOWNSLOPE FLOW...WILL RESULT IN CRITICALLY LOW HUMIDITIES. NO
PRECIPITATION IS EXPECTED.

LATEST MODEL RUNS INDICATE THAT DOWNSLOPE WESTERLY FLOW WILL
CONTINUE AT THE BURN SITE THROUGH FRIDAY NIGHT.  WINDS SPEEDS
WILL DECREASE THROUGH THE EVENING HOURS...BUT THE PREVAILING
FLOW WILL REMAIN WESTERLY.

THE WAY IT LOOKS RIGHT NOW...A COLD FRONT...ACCOMPANIED BY
EASTERLY WINDS AND HIGHER HUMIDITIES...WILL MOVE INTO THE
BURN SITES FROM THE EAST EARLY SATURDAY MORNING.  THE FRONT
SHOULD CONTINUE TO PUSH EAST UP INTO THE MOUNTAINS THROUGH
THE DAY...POSSIBLY LEADING TO SOME PRECIPITATION...IN THE
FORM OF SNOW ON THE SITE...BY SATURDAY EVENING.

NOTE...TEMPERATURES HAVE BEEN ADJUSTED DOWNWARD FROM WHAT
WAS DISCUSSED OVER THE PHONE BECAUSE A MORE REPRESENTATIVE
GRID BOX HAS BEEN CHOSEN.

.FRIDAY...

SKY/WEATHER.........MOSTLY SUNNY (35 PERCENT).
TEMPERATURES........50 AT 9 AM...56 AT NOON (APPROXIMATE - USE WITH CAUTION).
MAX TEMPERATURE.....58-63F.
HUMIDITY............22 PERCENT AT 9AM...18 PERCENT AT NOON (APPROXIMATE - USE WITH CAUTION).
MIN HUMIDITY........10-15 PERCENT.
20 FOOT WIND........WINDY. WEST WINDS 25-35 MPH. GUSTS 60-80 MPH.
MIXING HEIGHT.......5500 FT AGL.
TRANSPORT WIND......WEST AROUND 45 MPH.
SMOKE DISPERSAL.....POOR UNTIL 0700. EXCELLENT AFTER 1100.
HAINES INDEX........4 OR LOW POTENTIAL FOR LARGE PLUME DOMINATED
                    FIRE GROWTH.
LAL.................1.

.FRIDAY NIGHT...

SKY/WEATHER.........MOSTLY CLOUDY (60 PERCENT).
MIN TEMPERATURE.....27-32F.
MAX HUMIDITY........45-55 PERCENT.
20 FOOT WIND........WEST WINDS 15-25 MPH WITH GUSTS TO AROUND 45
                    MPH UNTIL 2400...THEN SOUTHWEST AROUND 8 MPH.
MIXING HEIGHT.......5500 FT AGL UNTIL 2000...THEN 1500 FT AGL.
TRANSPORT WIND......WEST AROUND 40 MPH UNTIL 2000...THEN AROUND 15
                    MPH.
SMOKE DISPERSAL.....EXCELLENT UNTIL 2000...THEN GOOD UNTIL
                    2100...THEN POOR.
HAINES INDEX........4 OR LOW POTENTIAL FOR LARGE PLUME DOMINATED
                    FIRE GROWTH.
LAL.................1.

.SATURDAY...

SKY/WEATHER.........MOSTLY CLOUDY. ISOLATED SNOW SHOWERS POSSIBLE
                    UNTIL 1200...THEN SCATTERED SNOW SHOWERS.
MAX TEMPERATURE.....35-40F.
MIN HUMIDITY........40-45 PERCENT.
20 FOOT WIND........EASTERLY AROUND 10 MPH.
MIXING HEIGHT.......4000 FT AGL.
TRANSPORT WIND......NORTHEAST AROUND 5 MPH.
SMOKE DISPERSAL.....POOR.
HAINES INDEX........2 OR VERY LOW POTENTIAL FOR LARGE PLUME
                    DOMINATED FIRE GROWTH.
LAL.................1.

$$
FORECASTER...WALROD
REQUESTED BY...VIRPI MATTSON
TYPE OF REQUEST...WILDFIRE
.TAG 20110428.SANDG.03/PUB