Area Forecast Discussion
Issued by NWS Denver/Boulder, CO

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FXUS65 KBOU 221032
AFDBOU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER/BOULDER CO
432 AM MDT TUE APR 22 2014

.SHORT TERM...(TODAY THROUGH TONIGHT )
ISSUED AT 432 AM MDT TUE APR 22 2014

HEATING ALREADY UNDERWAY AS PRESENT TEMPS ON THE PLAINS IN THE
UPPER 40S AND 50S ARE ON THE WAY TO HIGHS IN THE UPPER 70S AND
LOWER 80S THIS AFTERNOON. A TIGHT WEST-EAST PRESSURE GRADIENT WAS
INSTRUMENTAL IN PRODUCING THE STRONG...GUSTY SOUTHERLY WINDS ON
THE PLAINS FOR MOST OF THE NIGHT WHICH KEPT THE BOUNDARY LAYER
WELL MIXED. EVEN STRONGER WINDS WERE EVIDENT ON THE KFTG AND TDEN
WIND PROFILERS JUST A THOUSAND FEET OFF THE GROUND. BOTH PROFILERS
INDICATED A SOUTH WIND OF 45 KTS. HOWEVER IN THE PAST HOURS GROUND
LEVEL WINDS HAVE DECOUPLED FROM THE STRONGER FLOW ALOFT WITH
COOLING. THIS DOWNWARD TREND IN WIND SPEED SHOULD CONTINUE FOR THE
NEXT SEVERAL HOURS BEFORE STRENGTHENING ONCE AGAIN LATE THIS
MORNING AND AFTERNOON.

TODAY...STRONG UPPER LEVEL RIDGE SQUARELY OVER FRONT RANGE AT THIS
HOUR IS PROGGED TO MIGRATE SLOWLY EAST THROUGH THE DAY...PLACING
THE CWA UNDER MODERATE/STRONG SOUTHWEST FLOW ALOFT. AT THE
SURFACE...STRONG WARMING ALONG THE FRONT RANGE THIS MORNING WILL
RESULT IN STRONG PRESSURE FALLS AND A SFC TROUGH. MODELS SHOW
THIS TROUGH SHIFTING EAST ACROSS THE PLAINS DURING THE DAY. OUT
AHEAD OF THIS TROUGH SHOULD SEE GUSTY SOUTH-SOUTHEAST WINDS OF
20-30KTS REDEVELOP BY LATE MORNING OR EARLY AFTERNOON. BOUNDARY
LAYER AIR AHEAD OF THIS TROUGH IS ALSO SLIGHTLY MORE HUMID AND
UNSTABLE. IN THE WAKE OF THIS TROUGH...AIR WILL BE DRIER AND
LESS UNSTABLE. WEST-SOUTHWEST WINDS ALSO NOT AS STRONG. COULD SEE
ISOLATED TO SCATTERED SHOWERS/T-STORMS FORMING ALONE THIS
ADVANCING TROUGH OR DRYLINE FROM EASTERN DOUGLAS COUNTY TO
EASTERN WASHINGTON COUNTY BY AROUND MID-AFTERNOON. WITH STRONG
TRANSPORT WINDS...STORMS WILL BE FAST MOVERS. MODEL SOUNDINGS
INDICATE A POTENTIAL FOR STRONG DOWNBURST WINDS...ESPLY WITH
STORM MOTIONS OF 25-35KTS. HOWEVER...ITS PROBABLY NOT UNTIL LATE
THIS AFTERNOON WHEN THIS DRY LINE MOVES INTO MORE HUMID AIR ON THE
EAST-SOUTHEAST EDGE OF THE CWA THAT STORMS WILL PRODUCE MEASURABLE
RAINFALL...ALBEIT LIGHT. IN THE HIGH COUNTRY...SHOULD SEE A STEADY
INCREASE IN CLOUD COVER THROUGH THE DAY AS MOISTURE CONTINUES TO
STREAM IN FROM THE DESERT SOUTHWEST. SCATTERED RAIN SHOWERS AND
ISOLATED T-STORMS A REASONABLY GOOD BET IN THE HIGH COUNTRY BY
MID-AFTERNOON...WITH RAIN AMOUNTS GENERALLY UNDER A QUARTER INCH.

TONIGHT...SHOWERS AND STORMS ON THE PLAINS SHOULD END BEFORE MIDNIGHT
AS DRIER AIR SPREADING DOWN OF THE FRONT RANGE. GUSTY SOUTHWEST
WINDS WILL BE POSSIBLE AGAIN ON THE PLAINS WITH INCREASING
SOUTHWEST FLOW ALOFT. IN THE HIGH COUNTRY PARTLY TO MOSTLY CLOUDY
SKIES WILL PREVAIL AS THE UPPER TROUGH IN THE EASTERN GREAT BASIN
MOVES CLOSER TO THE STATE. COULD SEE A FEW RAIN/SNOW SHOWERS
LINGERING OVER THE HIGH ELEVATIONS ALL NIGHT.


.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 432 AM MDT TUE APR 22 2014

A STG UPPER LEVEL TROUGH WILL MOVE ACROSS THE NRN AND CNTRL ROCKIES
ON WED WITH NRN CO BEING ON THE FAR SRN END OF THIS SYSTEM.  ENOUGH
MOISTURE AND INSTABILITY WILL EXIST FOR A CHC OF SHOWERS IN THE MTNS
THRU THE AFTN.  OVER NERN CO A CDFNT WILL MOVE ACROSS THE PLAINS BY
EARLY AFTN WHICH MAY ALLOW FOR A SLIGHT CHC OF SHOWERS/TSTMS AS
WELL.  HIGHS OVER NERN CO WILL PEAK AROUND NOON AND THEN SLOWLY FALL
IN THE AFTN.  FOR NOW WILL KEEP READINGS IN THE MID 60S TO LOWER 70S
WITH THE WARMEST READINGS OVER THE FAR ERN PLAINS.  WINDS WILL BE
GUSTY AS WELL FM THE NW AND COULD BE ENHANCED BY ANY HIGH BASED
CONVECTION.

BY WED NIGHT DRIER AIR WILL EVENTUALLY SPREAD ACROSS THE AREA WITH
THE SHOWERS ENDING IN THE EVENING HOURS IN THE MTNS AND OVER THE
PLAINS.  WINDS COULD GET CLOSE TO HIGH WIND CRITERIA IN THE MTNS AND
FOOTHILLS LATE WED NIGHT INTO EARLY THU MORNING AS COMPONENT ALONG
WINDS INCREASE TO ABV 50 KTS AND MTN WAVE DEVELOPS.  ON THU THE FLOW
ALOFT WILL BE WNW WITH ONLY SOME HIGH LVL MOISTURE MOVING ACROSS SO
WILL KEEP FCST DRY.  HIGHS WILL RANGE FROM 65 TO 70 OVER NERN CO
BASED ON LATEST 850-700 MB TEMPS.

ON FRI THE FLOW ALOFT WILL BECOME MORE WSW AS A STG UPPER LEVEL
TROUGH MOVES INTO THE WEST COAST.  SOME MID AND HIGH LVL MOISTURE
WILL BE EMBEDDED IN THE FLOW HOWEVER LOWER LEVELS WILL BE DRY SO
WILL NOT MENTION ANY PCPN.  AS FOR HIGHS SHOULD SEE READINGS RISE
INTO THE LOWER TO MID 70S OVER NERN CO.

FOR THE WEEKEND HAVE VERY LITTLE CONFIDENCE IN CURRENT MODEL
SOLUTIONS WITH RESPECT TO HOW AN UPPER LEVEL STORM SYSTEM MAY EVOLVE
SOMEWHERE OVER THE CENTRAL ROCKIES AS A STG BLOCK DEVELOPS FM THE
NRN US INTO CENTRAL CANADA.

PREVIOUS 00Z AND 12Z GFS RUNS HAD A STG CLOSED LOW OVER SERN CO/NERN
NM WHILE THE LATEST GFS NOW HAS IT OVER NERN CO ON SUN.  ANALYSIS OF
GFS ENSEMBLE MEMBERS HAS THE CLOSED LOW FURTHER SOUTH OVER SERN
CO/TX PANHDL/SWRN KS.  MEANWHILE THE ECMWF HAS A CLOSED LOW
DEVELOPING EVEN FURTHER NORTH OVER WY ON SUN. LOOKING AT THE 00Z
FIM MODEL IT HAS SHIFTED THE STG CLOSED LOW INTO NERN CO ON SUN AS
WELL. SUFFICE TO SAY THERE IS A TREMENDOUS AMOUNT OF VARIABILITY
IN THE MEDIUM RANGE MODELS FM RUN TO RUN.

AHEAD OF THE SYSTEM ON SAT STG SFC LOW PRESSURE WILL DVLP FM CENTRAL
WY INTO SERN CO WITH SELY LOW LVL FLOW EAST OF THE MTNS.  DEPENDING
ON HOW MUCH HEATING OCCURS OVER THE PLAINS COULD SEE A ROUND OF STG
TSTMS SAT AFTN INTO SAT EVENING AS FLOW ALOFT WILL BE STRONGLY
DIFFLUENT.  MEANWHILE FM LATE SAT NIGHT INTO SUN THE ENTIRE FCST
WILL DEPEND ON WHERE THE STORM SYSTEM ENDS UP.  IF IT TAKES A MORE
SRN ROUTE ACROSS SRN COLORADO NATURALLY THE CHANCES FOR A
SIGNIFICANT SPRING STORM WOULD BE GREATER WHILE A MORE NRN TRACK
ACROSS NRN CO/WY WOULD LIMIT PCPN IN MOST AREAS EXCEPT POSSIBLY FOR
THE NRN MTNS. AT THIS POINT WILL JUST KEEP POPS MAINLY IN THE CHC
CATEGORY UNTIL IT BECOMES MORE CLEAR HOW THIS SYSTEM WILL EVOLVE.

&&

.AVIATION...(FOR THE TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 432 AM MDT TUE APR 22 2014

VFR CONDITIONS  AT DENVER AREA TERMINALS DURING THE NEXT 24
HOURS. WINDS WILL BE THE MAIN WEATHER CONCERN DURING THE PERIOD.
SOUTH- SOUTHWEST WINDS OF 8-14KTS THIS MORNING ARE EXPECTED TO
INCREASE TO 15-25KTS IN THE AFTERNOON...WITH EVEN STRONGER GUSTS
POSSIBLE WITH PASSING HIGH BASED SHOWERS AND/OR T-STORMS. LITTLE
RAIN EXPECTED FROM THEM. EXCEPTION TO THIS WILL BE KBJC WHERE
WINDS NOT EXPECTED TO BE AS STRONG. WIND SPEEDS WILL DECREASE SOME
OVERNIGHT...BUT REMAIN FROM A SOUTH-SOUTHWESTERLY DIRECTION.

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

$$

SHORT TERM...BAKER
LONG TERM...RPK
AVIATION...BAKER



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