Area Forecast Discussion
Issued by NWS Denver/Boulder, CO

Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
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 021047
AFDBOU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER/BOULDER CO
347 AM MST MON MAR 2 2015

.SHORT TERM...(TODAY THROUGH TONIGHT )
ISSUED AT 338 AM MST MON MAR 2 2015

STG SW FLOW ALOFT WILL CONTINUE TODAY IN ADVANCE OF A WEATHER
DISTURBANCE WHICH WILL MOVE ACROSS NRN AREAS TONIGHT.  SHOULD
CONTINUE TO SEE OROGRAPHIC SNOWS IN ZN 31 AND PORTIONS OF ZN 33 THRU
THIS AFTN ALTHOUGH ACTIVITY MAY DECREASE IN ZN 33 BY MIDDAY.  OVER
NERN CO A SFC LOW WILL BE NR DENVER WITH GUSTY SLY WINDS DEVELOPING
OVER THE PLAINS WITH DRY CONDITIONS EXPECTED THRU THE AFTN.  HIGHS
OVER NERN CO ARE GOING TO BE QUITE VARIABLE DUE TO LINGERING SNOW
COVER IN SOME AREAS.  IN ADDITION WITH A SFC LOW NR DENVER
CIRCULATION AROUND THIS LOW MAY ALLOW FOR LOW CLOUD COVER MUCH OF
THE DAY OVER NRN PORTIONS OF THE URBAN CORRIDOR INTO WELD COUNTY.
THUS READINGS OVER NRN AREAS OF URBAN CORRIDOR MAY NOT GET OUT OF
THE LOWER 30S WHILE SRNS ARAS RISE INTO THE LOWER TO MID 40S.  OVER
THE PLAINS WHERE SNOW COVER IS LESS READINGS COULD RISE WELL INTO
THE 40S WHERE GUSTY SSW WINDS OCCUR.

FOR TONIGHT A DISTURBANCE WILL TRACK ACROSS THE CO-WY BORDER AREA
WHICH WILL ENHANCE SNOWFALL IN THE MTNS WITH HEAVY SNOW IN ZNS 31
AND 33.  OVER NERN CO APPEARS DOWNSLOPE FLOW WILL BE IN PLACE THRU
THE EVENING HOURS BEFORE A STG CDFNT MOVES IN AFTER MIDNIGHT.
TIMING OF THIS FNT IS STILL NOT CERTAIN BUT IT WILL PROBABLY COME IN
FASTER THAN MODELS SHOW ONCE THE DISTURBANCE MOVES EAST OF THE AREA.
FOR NOW WILL HAVE IT NR THE WY BORDER BY MIDNIGHT AND THEN THRU
DENVER BY AROUND 3 AM OR SO.  QG FIELDS SHOW STG MID LVL DESCENT
LATE TONIGHT WITH INITIAL FNT PASSAGE SO NOT SURE HOW MUCH PRECIP
WILL DVLP AS BEST CHANCES MAY HOLD OFF UNTIL AFTER 12Z TUE.  FOR NOW
WILL KEEP HIGHEST POPS NR THE WY BORDER WITH ONLY CHC POPS AFTER
MIDNIGHT FURTHER SOUTH TOWARDS DENVER.

.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 346 AM MST MON MAR 2 2015

VERY STRONG WEST-SOUTHWESTERLY FLOW ALOFT IS ON THE DECREASE
TUESDAY FOR THE FORECAST AREA AS AN UPPER TROUGH MOVES THIS WAY.
BY TUESDAY NIGHT LATE...THE AXIS IS OVER THE CWA WITH MODERATE
WESTERLY FLOW AT THE JET LEVEL. THE TROUGH AXIS IS OVER THE FAR
EASTERN CWA BY 18Z WEDNESDAY. THE FLOW ALOFT IS WEAK AND WESTERLY
WEDNESDAY NIGHT WITH ANOTHER WEAK UPPER TROUGH TO OUR IMMEDIATE
WEST. THERE IS WEAK UPWARD QG VERTICAL VELOCITY FOR THE CWA
TUESDAY AFTERNOON THROUGH TUESDAY NIGHT. DOWNWARD SYNOPTIC SCALE
ENERGY IS PROGGED WEDNESDAY AND WEDNESDAY NIGHT. THE BOUNDARY
LAYER FLOW IS STRONG UPSLOPE ON TUESDAY INTO TUESDAY EVENING...
THEN MORE NORMAL DIURNAL PATTERNS ARE EXPECTED OVERNIGHT TUESDAY
NIGHT THROUGH WEDNESDAY NIGHT. FOR MOISTURE...IT LOOKS PRETTY DEEP
FOR THE MOUNTAINS TUESDAY MORNING...THEN FOR ALL THE CWA BY
AFTERNOON...CONTINUING THROUGH MUCH OF TUESDAY NIGHT. MODELS HAVE
SLOWED THINGS DOWN A BIT FROM YESTERDAY`S 00Z RUNS. MOISTURE
DECREASES ON WEDNESDAY FROM NORTHWEST TO SOUTH/SOUTHEAST. THINGS
ARE PRETTY MUCH DRIED OUT BY 00Z LATE WEDNESDAY AFTERNOON. THE
QPF FIELDS SHOW A TAD OF MEASURABLE SNOWFALL OVER THE MOUNTAINS
AND NORTHERN PLAINS TUESDAY MORNING...THE OVER THE WESTERN THREE
QUARTERS OF THE CWA BY AFTERNOON. THERE IS A BIT OVER ALL THE CWA
ON ALL THE MODELS ALL TUESDAY NIGHT. THERE IS TINY BIT PROGGED
OVER THE SOUTHERN HALF OF THE CWA WEDNESDAY MORNING. THEN EVEN
LESS JUST FOR THE SOUTH CENTRAL CWA WEDNESDAY AFTERNOON. THERE IS
NOTHING WEDNESDAY NIGHT. FOR POPS...THERE IS SOME HELP FROM
OROGRAPHICS IN THE MOUNTAINS AS WELL AS WEAK SYNOPTIC SCALE ENERGY
AND COLD AIR ADVECTION. WILL GO WITH 80% PLUS POPS TUESDAY INTO
TUESDAY EVENING THERE. THE FOOTHILLS AND ASSOCIATED PLAINS WILL
SEE STRONG COLD AIR ADVECTION AND PRETTY STRONG UPSLOPE IN THE
BOUNDARY LAYER. THE UPSLOPE IS NOT VERY DEEP HOWEVER...UNDER 700
MB ON ALL THE MODELS. WILL NEED 70% PLUS POPS IN THE THOSE AREAS
TO INTO THE EVENING TUESDAY ANYWAY. THE FURTHER EAST IN THE PLAINS
YOU GO WILL NEED LOWER POPS. WILL DIMINISH THE POPS EVERYWHERE
AFTER 06Z TUESDAY NIGHT...WITH SOME "CHANCE"S OF LESS OVER THE
SOUTHERN CWA WEDNESDAY MORNING.. AFTER THAT NO POPS THROUGH THE
EXTENDED. FOR TEMPERATURES...TUESDAY`S HIGHS ARE 9-16 C COLDER
THAN TODAY`S HIGHS. WEDNESDAY`S ARE CLOSE TO TUESDAY`S. FOR THE
LATER DAYS...THURSDAY THROUGH SUNDAY...THERE IS WEAK UPPER LEVEL
FLOW FOR THE CWA. THE DIRECTION OF THE FLOW IS GENERALLY
NORTHWESTERLY ALL FOUR DAYS WITH UPPER RIDGING AROUND. IT STILL
LOOKS DRY ALL FOUR DAYS...BUT TEMPERATURES LOOK TO STAY BELOW
SEASONAL NORMAL.

&&

.AVIATION...(FOR THE TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 338 AM MST MON MAR 2 2015

DENVER CYCLONE WAS LOCATED JUST WEST OF DIA WITH LOW CLOUDS AND
PATCHY FOG TO THE NW...NORTH AND EAST.  AT SOME POINT EXPECT LOW
CLOUDS AND FOG WILL EVENTUALLY AFFECT THE AIRPORT ONCE WINDS BECOME
MORE W OR NW IN THE 14Z-15Z TIME PERIOD.  MAY SEE DENSE FOG WITH
VISIBILITIES DOWN TO 1/4 FOR A FEW HOURS.  LATEST HRRR KEEPS LOW
CLOUDS AND SOME FOG AROUND THRU MUCH OF THE AFTN AS THE CYCLONE IS
LOCATED EAST OF DIA.  AS FOR WINDS THEY WILL BECOME LIGHT WNW BY MID
MORNING AND THEN NNW BY MIDDAY THRU MUCH OF THE AFTN.

FOR TONIGHT DEPENDING ON WHERE CIRCULATION CENTER IS COULD STILL SEE
SOME LINGERING LOW CLOUDS IN THE EVENING BEFORE LOW LVL FLOW BECOME
MORE WLY IN ADVANCE OF A CDFNT WHICH WILL ARRIVE AROUND 09Z.
GUSTY NLY WINDS WILL OCCUR WITH THE FNT PASSAGE WITH A CHC OF SOME
LIGHT SNOW HOWEVER AT THIS TIME IT APPEARS BEST CHC FOR SNOW WILL
BE AFTER 12Z ON TUE.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING UNTIL 5 PM MST TUESDAY FOR COZ031.

WINTER STORM WARNING FROM 5 PM THIS AFTERNOON TO 5 PM MST
TUESDAY FOR COZ033.

&&

$$

SHORT TERM...RPK
LONG TERM...RJK
AVIATION...RPK


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