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000
FXUS65 KBOU 140220
AFDBOU

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER/BOULDER CO
820 PM MDT MON MAY 13 2013

.UPDATE...


&&

.SHORT TERM...BROAD HIGH PRESSURE ALOFT REMAINS ACROSS THE REGION
WITH A LIGHT NORTHEAST FLOW ALOFT. THIS FLOW CONTINUES TO BRING
IN SOME HIGH LEVEL MOISTURE. 88D SHOWING THE LIGHT CONVECTION HAS
DIMINISHED THIS EVENING WITH A DRY FORECAST FOR THE REST OF THE
NIGHT. NO OTHER ISSUES.

.AVIATION...SURFACE WINDS HAVE ALREADY SHIFTED TO THE SOUTH AND
SOUTHWEST AT LOCAL TERMINALS FOLLOWING A BOUNDARY THAT HAS BEEN
MOVING NORTHEAST OUT OF DENVER. SCATTERED TO BROKEN CIRRUS WILL
CONTINUE THROUGH THE NIGHT. NO OTHER ISSUES.

&&

.PREV DISCUSSION... /ISSUED 317 PM MDT MON MAY 13 2013/

SHORT TERM...A WEAK WLY FLOW ALOFT WILL BE OVER THE CWFA THIS
EVENING WITH A BROAD RIDGE OF HIGH PRESSURE OVER NORTHERN
COLORADO. THE MDLS INDICATE ENOUGH MOISTURE WITH SOME MARGINAL
INSTBY FOR A FEW SHOWERS OR TSTMS OVER THE MOUNTAINS. ACROSS THE
NORTHEAST PLAINS IT WILL BE DRY IN THE LOWER LEVELS WITH JUST SOME
HIGH LEVEL MSTR LINGERING OVER THE REGION THIS EVENING. ON
TUESDAY ANOTHER VERY WARM AFTN ON TAP. THE FLOW ALOFT WILL REMAIN
WEAK. THE RIDGE WILL WEAKEN AS A SHORT WAVE PASSES TO THE NORTH
AND A DISORGANIZED UPPER LOW OVER THE DESERT SOUTHWEST SHIFTS
EAST. SFC BASED CAPES OVER THE MTNS AROUND 200 J/KG...SO WILL KEEP
A SLGT CHC OF TSTMS THERE. IT APPEARS TO BE TOO CAPPED OVER THE
URBAN CORRIDOR AND NORTHEAST PLAINS SO WL KEEP THAT AREA VOID OF
TSTMS THROUGH THE AFTN. ALTHOUGH IT WILL BE UNSEASONABLY
WARM NO FIRE WEATHER ISSUES AT THIS TIME DUE TO LGT WINDS AND
GREEN FUELS.

LONG TERM...THERE COULD BE AN INCREASE IN SHOWER/STORM ACTIVITY
TUESDAY EVENING AS THE AIRMASS MOISTENS WITH THE TROUGH PASSING
NORTH OF US. STILL LOOKING PRETTY MARGINAL THOUGH. NAM MOS CAME
OUT WITH VERY HIGH POPS FOR THE EVENING. GFS POPS LOOK LIKE OUR
FORECAST AND I WILL STICK WITH THAT...SLIGHT CHANCES WITH A BIT
MORE OVER THE FRONT RANGE MOUNTAINS. ON WEDNESDAY THERE IS MORE
MOISTURE...STILL LOOKING LIKE A 10-15 DEGREE TEMPERATURE DROP ON
THE PLAINS WITH ONLY SLIGHT COOLING ALOFT. PROBABLY TOO STABLE FOR
THUNDERSTORMS ON THE PLAINS...NOT MUCH CHANGE OVER THE MOUNTAINS.
COULD HAVE SOME ORGANIZED SHOWERS FORM IN THE FOOTHILLS
CONVERGENCE IN THE AFTERNOON AND DRIFT SE...POSSIBLY WARM ENOUGH
BY THE END OF THE DAY FOR CONVECTION TO SURVIVE FOR A WHILE AS IT
MOVES EASTWARD.  ALL THIS IS ALREADY COVERED.

NOT MUCH TO CHANGE IN THE REST OF THE PERIOD EITHER. LIGHT WEST
FLOW ALOFT WILL BECOME SW AND INCREASE ON FRIDAY AHEAD OF THE NEXT
TROUGH. PRETTY GOOD AGREEMENT NOW ON TIMING ON SATURDAY...GFS IS
STRONGER THAN THE ECMWF AND WOULD HAVE A BIT MORE COOLING...OLD
FORECAST IS SIMILAR TO TODAYS MODEL CONSENSUS. SOME INCREASE IN
MOISTURE BUT AGAIN IT DOES NOT LOOK LIKE A LOT. FOR SUNDAY AND
MONDAY NORTHWEST FLOW WITH COLORADO ON THE EDGE OF THE MOISTURE
AND INSTABILITY. HINTS OF ANOTHER SHORTWAVE MONDAY WHICH IS
PRETTY WEAK IN SOME OF THE RUNS BUT MAY REINFORCE THE COOLER AIR
AND PROVIDE A LITTLE LIFT IN THE STRONGER VERSIONS. THE STRONGER
GFS RUNS COULD PUT US BACK INTO THE 60S SUNDAY AND MONDAY...BUT
THE CONSENSUS NUMBERS IN THE 70S ARE FINE FOR NOW.

AVIATION...NO ISSUES TO CONTEND WITH OVER THE NEXT 24 HRS WITH
VFR CONDITIONS ANTICIPATED. WEAK E/NELY WINDS THIS AFTN SHOULD
TRANSITION OF DRAINAGE THIS EVENING. SIMILAR PATTERN CAN BE
EXPECTED ON TUESDAY. AMS APPEARS TOO CAPPED FOR TSTMS THROUGH
TUESDAY AFTN...WITH JUST ISOLD DEVELOPMENT POSSIBLE SOUTH AND
WEST OF DENVER AFTER 19Z.

HYDROLOGY...NO ISSUES AT THIS TIME.

&&

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

$$

SHORT TERM...ENTREKIN
LONG TERM....GIMMESTAD
AVIATION...ENTREKIN