Area Forecast Discussion
Issued by NWS Denver/Boulder, CO

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS65 KBOU 300242
AFDBOU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER/BOULDER CO
842 PM MDT SAT AUG 29 2015

.UPDATE...
ISSUED AT 832 PM MDT SAT AUG 29 2015

MAINLY DRY AIRMASS OVER EASTERN COLORADO WITH MODERATE INVERSION
AT 500MB NOTED ON 00Z DNR SOUNDING. STILL A FEW LIGHT SHOWERS
OVER THE DIVIDE AND PARK COUNTY AND EXPECT THESE TO DISSIPATE BY
LATER THIS EVENING. NO CHANGES PLANNED TO CURRENT FORECAST.

&&

.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 405 PM MDT SAT AUG 29 2015

SMOKEY SKIES GENERALLY EAST OF THE MTNS THE PRODUCT OF SEVERAL
ACTIVE WILDFIRES SCATTERED ACROSS THE PACIFIC NORTHWEST AND
NORTHERN ROCKY MTN REGION. SMOKE HAS THINNED THOUGH THIS WITH
STG HEATING AND MIXING. MEANWHILE LOW INTENSITY CONVECTION NOW
UNDERWAY OVER THE HIGH TERRAIN TO THE WEST- SOUTHWEST OF HE
DENVER METRO AREA. NOT SEEING ANY LIGHTNING BUT RADAR IS DETECTING
A RIBBON OF LIGHT PRECIP UP ALONG THE CONTINENTAL DIVIDE IN PARK
AND SUMMIT COUNTIES. AT PRESENT TIME...STILL UNDER A STRONG/VERY
WARM UPPER RIDGE. RIDGE AXIS ABOUT TO PASS OVER THE AREA AS RAP
MODEL. SHOULD SEE LIGHT N-NWLY FLOW ALOFT TURNING SWLY NEXT
SEVERAL HOURS WITH SPEEDS NOT MUCH GREATER. THE SHIFT SHOULD HELP
TO DEFLECT SOME OF THIS SMOKE OUT OF HERE. UPSTREAM...STRONGER
SWLY FLOW WITH AN 80-90KT JET CORE OVER NERN NEVADA/NWRN UTAH/ERN
IDAHO IS PROGGED TO MAKE ITS WAY EASTWARD OVER THE NEXT 24 HOURS.
MID/HIGH- LEVEL MOISTURE ALIGNED WITH THIS JET WILL SPREAD OVER
WRN COLORADO TONIGHT AND SUNDAY MORNING. MODEL CROSS SECTIONS AND
SOUNDINGS SHOW CONDENSATION LEVELS LOWERING OVER THE HIGH COUNTRY
THROUGH THE DAY WITH THE POSSIBILITY OF SCATTERED SHOWERS/T-STORMS
FORMING BY LATE MORNING OR EARLY AFTERNOON PRETTY MUCH FROM THE
CONTINENTAL DIVIDE WESTWARD. BY LATE AFTERNOON SHOULD SEE SWLY
FLOW ALOFT CONTINUE TO STRENGTHEN AS THE CORE OF MOISTURE ALIGNING
WITH THE CONT DIVIDE. EAST OF THE MTNS...ATMOSPHERE SHOULD
ESSENTIALLY REMAIN TOO DRY AND PRETTY MUCH CAPPED AT MID-LEVELS.
STILL...CAN NOT RULE OUT A STRAY STORMS OR TWO DRIFTING NORTHEAST
OFF THE FRONT RANGE LATE IN THE AFTERNOON. WILL GO WITH SCATTERED
POPS IN THE HIGH COUNTRY DURING THE AFTERNOON AND ONLY A 10 PCT
POP ALONG THE BASE OF THE FOOTHILLS LATE. OTHERWISE...SEE LITTLE
CHANGE IN TEMPERATURE NEXT 24 HOURS. LASTLY...WIND SPEEDS AND MIN
RH VALUES ARE FCST TO REMAIN ABOVE RED FLAG CRITERIA ON SUNDAY.


.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 405 PM MDT SAT AUG 29 2015

AREA OF MOISTURE WILL DRAG ACROSS COLORADO SUNDAY NIGHT INTO
MONDAY. THERE IS ONLY SLIGHT COOLING ALOFT AND THE CLOUD COVER
WILL HOLD BACK SURFACE TEMPERATURES A LITTLE...SO INSTABILITY WILL
BE LIMITED. CURRENT FORECAST HAS CHANCE POPS MOUNTAINS AND SLIGHT
CHANCES PLAINS THROUGH THIS PERIOD AND THAT LOOKS SUFFICIENT.

DRIER AIR ALOFT WILL MOVE IN MONDAY NIGHT AND TUESDAY. WITH MORE
SUNSHINE THIS COULD ACTUALLY INCREASE CONVECTION A BIT
TUESDAY...THOUGH WITH LIGHT SOUTHWEST FLOW ALOFT WE MAY START TO
SEE SOME DRYING FROM MIXING ALONG THE FRONT RANGE. FOR NOW WILL
PLAN ON SIMILAR OR A BIT LESS COVERAGE...BUT COULD HAVE AN UPTICK
IN STORM INTENSITY.

FOR THE REST OF THE WEEK WE ARE IN LIGHT SW FLOW ALOFT WITH DRY
AIR ALOFT...AND WE SHOULD HAVE A DECENT DRYLINE NEAR THE EASTERN
BORDER. FOR THE MOST PART EXPECT CONVECTION TO BE CAPPED...BUT
COULD HAVE STRONG CONVECTION STARTING ON THE DRYLINE IF SOME SMALL
FOCUSING FEATURE APPEARS. STILL COULD HAVE SOME MINOR MOUNTAIN
CONVECTION AS WELL BUT IT LOOKS PRETTY MINIMAL. DECENT AGREEMENT
ON A SHORTWAVE PASSING OVER THE NORTHERN ROCKIES ABOUT
SATURDAY...GFS HAS A WEAK SHALLOW FRONT WHILE THE EC HAS A BIT
STRONGER IMPACT. MAIN EFFECT IS PROBABLY A LITTLE COOLING SATURDAY
OR SUNDAY WITH LOW LEVEL MOISTENING...UNSURE OF THE EFFECT ON
STABILITY BUT IT LOOKS LIKE MOST OF THE FORCING WILL BE NORTH OF
US. COULD SET THE STAGE FOR MORE ACTIVITY AGAIN SUNDAY/MONDAY.

FINALLY...THE SMOKE. CURRENT BATCH OF SMOKE COMING OFF THE SIERRAS
WILL BE MAINLY NORTH OF US AND THE SOUTHWEST FLOW ALOFT SHOULD
KEEP MOST OF THE HIGHER LEVEL SMOKE GOING THAT WAY. WE WILL OF
COURSE BE ON THE EDGE OF IT THOUGH. HOWEVER...THE LOW LEVEL AIR WE
GET BEHIND THE FRONTS MIGHT BE PRETTY BAD. EXPECTING ANOTHER
SURGE OF SMOKE WITH THE FRONT MONDAY THAT MIGHT STALL OVER US LIKE
THE LAST TWO DID. I WOULD LIKE TO THINK THERE WOULD BE SOME MIXING
OUT ON TUESDAY/WEDNESDAY BUT THERE MIGHT NOT BE MUCH TO DILUTE IT
WITH LIGHT SURFACE WINDS AND SOME SMOKE AT HIGHER LEVELS FROM
CALIFORNIA. AND YES...WE WILL PROBABLY BE IN THE SAME SITUATION
AGAIN NEXT WEEKEND AS ANOTHER TROUGH STIRS UP WINDS FROM
CALIFORNIA NORTHWARD FRIDAY/SATURDAY AND THEN PUSHES A FRONT INTO
COLORADO OVER THE WEEKEND. YUCK.

&&

.AVIATION...(FOR THE TAFS THROUGH 06Z SUNDAY EVENING)
ISSUED AT 832 PM MDT SAT AUG 29 2015

SOUTHEAST WINDS AT SUSTAINED 15-20KT WILL GRADUALLY SHIFT MORE
SOUTHERLY AND WEAKEN SOME AFTER MIDNIGHT AT LOCAL TERMINALS.
AIRMASS STILL DRY BUT SOME HIGH CIRRUS AND SMOKE WILL REMAIN IN
THE AIR.

&&

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

$$

UPDATE...ENTREKIN
SHORT TERM...BAKER
LONG TERM...GIMMESTAD
AVIATION...ENTREKIN



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.