National Weather Service Weather Forecast Office

• Home
• Site Map
• News
• Organization
• Search for: NWS All NOAA 

000
FXUS65 KBOU 171539
AFDBOU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER/BOULDER CO
939 AM MDT MON JUN 17 2013

.UPDATE...


&&

.SHORT TERM...OVERALL MOISTURE LEVELS ARE SIMILAR TO YESTERDAY
WITH PW VALUES AROUND .6" OF AN INCH OVER THE FRONT RANGE. A WEAK
SURGE HAS MOVING MOVING SOUTH ACROSS THE PLAINS EARLY THIS MORNING
AS WINDS HAVE SHIFTED NORTHEAST AND DEWPOINTS HAVE RISEN BACK INTO
THE LOWER 50S OVER THE NORTHERN FRONT RANGE FROM ERIE NORTHWARD TO
THE WYOMING BORDER. MODELS NOT DOING VERY WELL WITH THIS
ESPECIALLY THE NAM. NAM SEEMS WAY TOO DRY AND WILL DISCOUNT. THE
MAIN THREAT WILL STILL BE ON THE EASTERN PLAINS TODAY WITH UPPER
40S/LOWER 50S DEWPOINTS AND SURFACE BASED CAPES PROGGED FROM
1000-2000J/KG. WOULD STILL EXPECT THE LOW LEVEL MOISTURE TO MIX
OUT OVER THE FRONT RANGE BUT WITH THIS WEAK SURGE MIGHT BE ABLE TO
HOLD IT IN A BIT LONGER THAN MODELS INDICATE. WILL MONITOR IN
CASED POPS NEED TO BE INCREASED OVER THE FRONT RANGE. WILL STILL
KEEP THE MAIN SEVERE THREAT ON THE PLAINS AND EAST OF THE DENVER
AREA/URBAN CORRIDOR.

.AVIATION...WITH THE WEAK SURGE...SURFACE WINDS SHIFTING TO THE
NORTHEAST. WINDS WILL GRADUALLY SHIFT TO A MORE EASTERLY
COMPONENT THIS AFTERNOON. STILL LOOKING FOR ISOLATED STORMS LATER
THIS AFTERNOON WITH GUSTY AND VARIABLE WINDS THE MAIN THREAT. IF
WE CAN HOLD ONTO LOW LEVEL MOISTURE A BIT LONGER THAN STORMS MAY
BE STRONGER.

&&

.PREV DISCUSSION... /ISSUED 356 AM MDT MON JUN 17 2013/

SHORT TERM...UPPER LEVEL RIDGE WILL EXTEND FROM THE SOUTHERN
ROCKIES NORTH TO THE NORTHERN ROCKIES. THIS WILL RESULT IN A
WESTERLY FLOW ALOFT. AT THE SURFACE...A LOW PRESSURE TROUGH WILL BE
DRAPED ACROSS CENTRAL COLORADO. THIS WILL CAUSE SURFACE WINDS TO
BECOME EASTERLY AND PULL MOISTURE INTO EASTERN COLORADO. AIRMASS
ABOVE THE LOW LEVEL EAST WINDS WILL BE DRY AND WILL MIXED DOWN ALONG
THE FRONT RANGE THIS AFTERNOON AND CAUSE DEW POINTS TO FALL INTO TO
30S. EVEN THOUGH THE AIRMASS WILL BE DRY WEST OF I-25...STEEP MID
LEVEL LAPSE RATES SHOULD TRIGGER ISOLATED TO SCATTERED SHOWERS AND
STORMS. DUE TO THE LIMITED MOISTURE AND INSTABILITY...THE STORMS
WILL WEAK AND PRODUCE LIGHT TO MODERATE RAINFALL AND GUSTY OUTFLOW
WINDS.

OVER THE EASTERN PLAINS MOISTURE WILL BE DEEPER AND DEW POINTS WILL
BE ABLE TO STAY IN THE UPPER 40S TO MID 50S. THESE DEW POINTS ALONG
WITH HIGHS IN THE MID 80S WILL PRODUCE CAPES OF 1000-2000 J/KG. IN
ADDITION TO THE GOOD INSTABILITY...EASTERLY LOW LEVEL WINDS AND
WESTERLY WINDS ALOFT WILL PROVIDE ENOUGH SHEAR TO PRODUCE A FEW
SUPER CELLS. LARGE HAIL AND DAMAGING WILL BE THE MAIN THREAT WITH
THE STRONGER STORMS. APPEARS THE BEST CHANCE FOR SEEING SEVERE
STORMS WILL BE EAST OF A LINE FROM FORT MORGAN TO LIMON.

LONG TERM...NOT MUCH CHANGE IN THE PATTERN FOR TUESDAY. THE UPPER
LEVEL WESTERLY FLOW WILL BE FAIRLY WEAK WITH THE RIDGE AXIS OVER
EASTERN COLORADO BY 00Z WEDNESDAY. THE MDLS MAINTAIN THE LOW LEVEL
MOISTURE OVER THE NORTHEAST PLAINS OF COLORADO...WITH THE
POTENTIAL FOR TSTMS IN THE AFTN AND EVENING HIGHEST EAST OF THE
URBAN CORRIDOR. FAVORABLE DIRECTIONAL SHEAR AND CAPE (AT OR ABOVE
1500 J/KG0 FOR A FEW SEVERE TSTMS. TUESDAY NIGHT AND WEDNESDAY...
THE UPPER RIDGE CONTINUES TO TRANSLATE EASTWARD AND THE FLOW ALOFT
BECOMING DRY AND SOUTHWESTERLY. AS A RESULT...THE THREAT OF
THUNDERSTORMS WILL DIMINISH WITH JUST A SLGT CHC OF THUNDERSTORMS
OVER THE FAR NORTHEAST PLAINS. THE FLOW ALOFT WILL INCREASE OUT OF
THE SOUTHWEST ON THURSDAY AND FRIDAY...AS A CLOSED LOW OVER THE
PAC NW SLOWLY MOVES INTO THE NRN ROCKIES. CONSEQUENTLY...TEMPERATURES
WILL RISE AND THE RELATIVE HUMIDITIES IN THE AFTN WILL DROP. THE
END RESULT WILL BE AN ELEVATED FIRE DANGER FOR THURSDAY AND FRIDAY.
AREAS OVER SOUTH PARK...THE FRONT RANGE FOOTHILLS AND PALMER
DIVIDE WILL LIKELY BE THE DRIEST. THE MDLS HINT AT SOME COOLING
OVER THE WEEKEND WITH THE FLOW ALOFT DECREASING. IN ADDITION...THERE
IS A HINT OF SOME SUBTROPICAL MOISTURE CLIPPING SRN AND ERN
PORTIONS OF CO ON SATURDAY. AS THE TROUGH OVER THE NRN ROCKIES
SLIDES EASTWARD ALONG THE CANADIAN BORDER ON SUNDAY...THE MDLS
ALSO INDICATE AN ASSOCIATED COLD FRONT POSSIBLY SLIPPING INTO THE
NERN PLAINS AROUND 00Z MONDAY.

AVIATION...WINDS WILL BECOME LIGHT AFTER 12Z AND THEY SHIFT TO THE
EAST BY 18Z. ISOLATED TO SCATTERED THUNDERSTORMS WILL AGAIN DEVELOP
AND BE POSSIBLE AFTER 20Z. GUSTY OUTFLOW WINDS TO 40 KNOTS WILL BE
POSSIBLE WITH THE STORMS. LOW CLOUDS AND PATCHY FOG ARE OVER FAR
NORTHEAST COLORADO AT THIS TIME. JUST A SLIGHT CHANCE OF THEM MOVING
INTO THE DENVER AREA AND WILL LEAVE THEM OUT OF THE TAF FOR NOW.

HYDROLOGY...SIMILAR CONDITIONS WILL PREVAIL AS THE LAST COUPLE OF
AFTERNOONS WITH ISOLATED TO SCATTERED THUNDERSTORMS EXPECTED OVER
THE BURN SCARS. AIRMASS WILL CONTINUE TO BE ON THE DRY SIDE AND THE
STORMS THAT DO DEVELOP WILL BE MOVING AT 15 TO 25 MPH. THE THREAT
FOR PROLONGED HEAVY RAIN OVER THE BURN AREAS WILL REMAIN CLOSE TO
ZERO.

&&

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

$$

SHORT TERM...ENTREKIN
LONG TERM....COOPER
AVIATION...ENTREKIN