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 210843
AFDBOU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER/BOULDER CO
243 AM MDT TUE APR 21 2015

.SHORT TERM...(TODAY THROUGH TONIGHT )
ISSUED AT 210 AM MDT TUE APR 21 2015

NW FLOW ALOFT WILL BE OVER THE RGN THRU TONIGHT.  A WEAK DISTURBANCE
EMBEDDED IN THE FLOW MAY MOVE ACROSS NRN CO LATE THIS AFTN INTO THE
EARLY EVENING HOURS.  THERE WILL BE ENOUGH MOISTURE COMBINED WITH
DECENT LAPSE RATES FOR SCT SHOWERS AND ISOLD STORMS OVER THE
HIGHER TERRAIN THIS AFTN WITH WDLY SCT ACTIVITY ALONG THE FRONT
RANGE MAINLY THIS EVENING. AS FOR HIGHS 850-700 MB TEMPS WOULD
SUPPORT HIGHS IN THE 60S ACROSS NERN CO THIS AFTN. FOR TONIGHT
PRECIP CHANCES SHOULD DECREASE BY MID TO LATE EVENING AS THE
DISTURBANCE EXITS NE COLORADO.

.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 210 AM MDT TUE APR 21 2015

THE MDLS APPEAR TO BE FAIRLY SIMILAR WITH THE TIMING OF
THE OVERALL PATTERN FROM WEDNESDAY INTO THE WEEKEND.  ON WEDNESDAY A
WEAK UPPER LEVEL RIDGE AXIS WILL MOVE ACROSS COLORADO.  THE FLOW
ALOFT WILL BE FAIRLY WEAK...TRANSITIONING FROM NORTHWEST/WESTERLY
THROUGH THE DAY AS WEAK UPPER LEVEL RIDGE AXIS SHIFTS FM UTAH INTO
WESTERN COLORADO.  SOME MID LEVEL MOISTURE DOES MOVE OVER WESTERN CO
THROUGH THE DAY.  IN ADDITION...SOME LOW LEVEL CONVERGENCE ALONG THE
FRONT RANGE WITH SFC EAST TO SOUTHEASTERLY WINDS IN THE AFTN WHICH
WOULD INDUCE A DENVER CYCLONE. STRONGEST SHEAR WOULD BE IN THE LOW
LEVELS...WITH THE WEAKER FLOW ALOFT.  NAM12 FORECAST CAPES AROUND
900 J/KG BY LATE IN THE AFTN. STABILITY OF THE AIRMASS INCREASES
FURTHER EAST.  ON THURSDAY...THE FLOW ALOFT WEAK AND SWLY AS THE
RIDGE AXIS TRANSLATE EASTWARD.  THERE WILL BE A SURFACE TROF OVER
EASTERN COLORADO.  THE LOWER LEVELS WILL BE DRIER BUT ENOUGH MID
LEVEL MOISTURE AROUND TO GO WITH MORE AFTN/EVNG TSTMS.  CAPES IN
DENVER AROUND 500 J/KG IN THE AFTN.  THURSDAY NIGHT...THE MDLS
BRINGS THE UPPER TROUGH OVER BAJA CA INTO ARIZONA BY 12Z FRIDAY...
THEN ACROSS SOUTHERN AND EASTERN COLORADO FRIDAY AFTN AND FRIDAY
NIGHT.  MODERATE MID AND UPPER LEVEL QG ASCENT WITH THIS SYSTEM OVER
THE SOUTHERN PART OF THE CWA WITH SOME EMBEDDED TSTMS WITH ITS
PASSAGE FRIDAY AFTN/EVNG.  THE WEEKEND WILL REMAIN UNSETTLED...THE
MDLS BRING A SECONDARY TROUGH ACROSS NORTHERN COLORADO LATE SATURDAY
INTO SUNDAY FOR ANOTHER ROUND OF SHOWERS/PSBL TSTMS. THE AIRMASS
DOES NOT APPEAR TO DRY OUT UNTIL EARLY NEXT WEEK...WHEN A STRONGER
UPPER LEVEL RIDGE ESTABLISHES ITSELF OVER THE CENTRAL
ROCKIES...MONDAY INTO TUESDAY.

&&

.AVIATION...(FOR THE TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 210 AM MDT TUE APR 21 2015

WINDS HAVE BECOME DRAINAGE EARLY THIS MORNING AND WILL BECOME MORE
WSW BY 15Z OR SO.  BY EARLY AFTN WINDS WILL BECOME MORE NWLY AND
THEN NLY BY 23Z AS A WEAK COOL FNT MOVES ACROSS. BY EARLY EVENING
WINDS SHOULD GRADUALLY SHIFT BACK TO DRAINAGE BY 03Z.

AS FAR AS PCPN THERE MAY BE SOME WDLY SCT HIGH BASED SHOWERS IN THE
22Z-02Z TIME PERIOD WITH AN ISOLD TSTM POSSIBLE HOWEVER WILL JUST
MENTION VCSH IN THE NEXT TAF.

&&

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

$$

SHORT TERM...RPK
LONG TERM...COOPER
AVIATION...RPK



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