Area Forecast Discussion
Issued by NWS Denver/Boulder, CO

Home | Current Version | Previous Version | Graphics & Text | 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 172219 CCA
AFDBOU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER/BOULDER CO
310 PM MST WED DEC 17 2014

.SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 310 PM MST
WED DEC 17 2014

FREEZING DRIZZLE HAS BEEN REPORTED ACROSS THE BORDER IN KANSAS AND
NEBRASKA THIS MORNING...BUT HAVE SEEN NO EVIDENCE HERE IN COLORADO.
THIS WILL BE ONE THING FOR THE EVENING SHIFT TO CONSIDER AS  IF
FEEDER-SEEDER ISSUES DEVELOP.  THERE HAS BEEN SOME RESIDUAL FOG IN
NORTHEAST COLORADO AND ADDED FOG THIS EVENING TO THE NORTHEAST
CORNER.  AS A RESULT OF THE SNOW COVER AND FOG...THE MAX TEMPS HAVE
REMAINED IN THE 20S TODAY.

THE UPPER LEVEL WEATHER SYSTEM WILL LIFT ACROSS SOUTHEAST COLORADO
THIS EVENING.  RADAR ALREADY SHOWS ECHOES ACROSS THE PALMER
DIVIDE... BUT THUS FAR NOTHING HAS BEEN REPORTED AT THE SURFACE.
WILL LEAVE POPS IN THE FORECAST ESPECIALLY OVER THE PALMER DIVIDE...
BUT EXPECT ONLY A TRACE OF SNOW AWAY FROM THE PALMER DIVIDE...MAY
SEE AN INCH OR SO ON THE DIVIDE.

IN THE MOUNTAINS...SNOW WILL CONTINUE TONIGHT AND THURSDAY.  THE
FIRST DISTURBANCE WILL BE FOLLOWED ON THURSDAY WITH A TROUGH DIVING
INTO ARIZONA.  AS A RESULT SNOW WILL STILL LINGER IN THE MOUNTAINS
WITH THE DRYING HOLDING OFF UNTIL THURSDAY NIGHT.

TEMPERATURES WILL BE COLD TONIGHT WITH TEENS OVER THE SNOWFIELD IN
NORTHEAST COLORADO...SINGLE DIGITS AND TEENS IN THE MOUNTAINS AND
20S OVER THE URBAN CORRIDOR.  THURSDAY WILL FEATURE A SLIGHT WARMUP
TO NEAR FREEZING IN NORHTEAST COLORADO...AND AROUND 40 ALONG THE
URBAN CORRIDOR.

.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 310 PM MST WED DEC 17 2014

WEAK UPPER TROUGH MOVES INTO THE CENTRAL PLAINS STATES ON FRIDAY
WITH A NORTHWEST FLOW ALOFT DEVELOPING OVER COLORADO. THERE WILL BE
JUST ENOUGH MOISTURE AVAILABLE TO PRODUCE SCATTERED LIGHT SNOW
SHOWERS OVER THE MOUNTAINS THURSDAY EVENING. SNOW CHANCES SHOULD
DECREASE AFTER MIDNIGHT AS WEAK RIDGING AND DOWNWARD FORCING MOVES
INTO THE REGION. DRY WEATHER AND NEAR NORMAL TEMPERATURES WILL
CONTINUE OVER THE PLAINS THROUGH SATURDAY. SOME WEAK DOWNSLOPE FLOW
WILL KEEP FRIDAY MORNING LOW TEMPERATURES UP FROM PREVIOUS MORNINGS
ALONG THE FRONT RANGE URBAN CORRIDOR.

MAJOR CHANGE IN THE PATTERN OVERNIGHT SATURDAY INTO SUNDAY AS STRONG
AND MOIST JET STREAM MOVES INTO COLORADO FROM THE NORTHWEST. THIS
PATTERN LOOKS TO BE SETTING UP A PROLONGED PERIOD OF SNOW AND WIND
ACROSS THE MOUNTAINS FROM SUNDAY THROUGH THE END OF THE PERIOD. SNOW
AND WIND ARE EXPECTED TO INCREASE ACROSS THE MOUNTAINS DURING THE
DAY ON SUNDAY...HOWEVER...WARM AIR ADVECTION SHOULD KEEP THE SNOW ON
THE LIGHT SIDE. DRY WEATHER AND SLIGHTLY ABOVE NORMAL TEMPERATURES
ARE EXPECTED ON THE PLAINS DUE TO DOWNSLOPE FLOW. CROSS SECTIONS
ALSO SHOW WINDY CONDITIONS OVER THE FRONT RANGE FOOTHILLS FROM LATE
SUNDAY THROUGH ABOUT NOON MONDAY.

FROM MIDDAY MONDAY THROUGH TUESDAY MORNING...THE GFS AND ECMWF SHOW
A NORTH NORTHWEST TO SOUTH SOUTHEAST ORIENTED 140+ KT JET MAX OVER
CENTRAL COLORADO. THIS COMBINED WITH PLENTY OF MOISTURE AND COLD AIR
ADVECTION...WILL BRING THE POTENTIAL FOR HEAVY SNOW AND VERY WINDY
CONDITIONS TO THE HIGH COUNTRY. WARM ADVECTION WILL MOVE INTO THE
MOUNTAINS DURING THE DAY ON TUESDAY AS THE UPPER JET MOVES OVER
EASTERN COLORADO. THIS SHOULD RESULT IN A DECREASE IN SNOW
INTENSITY. HOWEVER...WINDY CONDITIONS AND LIGHT SNOW SHOULD STILL
PERSIST. MONDAY AND TUESDAY LOOK TO BE SOMEWHAT WINDY ON THE PLAINS
AS A GRADIENT SETS UP BETWEEN A SURFACE LOW OVER THE NORTHERN PLAINS
AND HIGER PRESSURE OVER WESTERN COLORADO. THE NORTHWEST WINDS SHOULD
KEEP OVERNIGHT LOWS ON MONDAY MORNING AT ABOVE NORMAL LEVELS. THE
GFS AND ECMWF ARE HINTING AT SOME ANTICYCLONIC TURNING ON
MONDAY...WHICH MAKES ITS WAY INTO THE DENVER AREA BY 00Z TUESDAY. IF
THIS HAPPENS, I WOULDN`T BE SURPRISED TO SEE SOME SNOW BANDS OVER
THE NORTHEASTERN PLAINS MONDAY MORNING MOVING INTO THE DENVER AREA
BY AFTERNOON. THEREFORE...I HAVE INCREASED THE POPS ON MONDAY FOR
THESE AREAS.

LOOKING FURTHER AHEAD TO THE CHRISTMAS HOLIDAY...THE UPPER JET
CONTINUES ORIENTED OVER THE COLORADO WHICH SHOULD KEEP SNOW FALLING
OVER THE HIGH COUNTRY. THE GFS AND ECMWF BOTH SHOWING THE
POSSIBILITY OF LIGHT SNOW ACROSS THE FRONT RANGE URBAN CORRIDOR
CHRISTMAS EVE DAY. FOR NOW HAVE ONLY ADDED A 10 POP FOR DENVER DUE
TO THE FACT THAT THIS IS WAY OUT IN DAY SEVEN.

&&

.AVIATION...(FOR THE TAFS THROUGH 00Z WEDNESDAY LATE AFTERNOON)
ISSUED AT 310 PM MST WED DEC 17 2014

SKIES WILL REMAIN VFR THROUGH THROUGH 5PM...THEN THERE MAY BE SOME
MVFR CEILINGS AND VISIBILITIES WITH SCATTERED SNOW SHOWERS THIS
EVENING.  SOME FOG WILL REDEVELOP ON THE PLAINS...BUT IS EXPECTED TO
REMAIN WELL EAST OF THE METRO AREA.

VFR CONDITIONS WILL RETURN AFTER MIDNIGHT AS DRYER SUBSIDENCE MOVES
INTO THE AREA.

&&

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

$$

SHORT TERM...RTG
LONG TERM...KALINA
AVIATION...RTG



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