Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 04/21/14
AREA FORECAST DISCUSSION
NWS PUEBLO CO
854 PM MDT SUN APR 20 2014
.UPDATE...
ISSUED AT 850 PM MDT SUN APR 20 2014
UPDATED TO TREND POPS WITH THE LATEST RADAR DATA. SINCE SUN
DOWN...MOST OF THE SHOWER ACTIVITY HAS DISSIPATED ACROSS SOUTHERN
COLORADO. THE EXCEPTIONS ARE OVER THE PALMER DIVIDE WHERE NEW
DEVELOPMENT HAS BEEN PUSHING SOUTH...AND OVER THE EASTERN
MOUNTAINS AND ADJACENT PLAINS WEST OF I-25 WHERE WEAK ACTIVITY
CONTINUES. HAVE MAINTAINED THESE AREAS SEEING SHOWER ACTIVITY AND
ISOLATED THUNDERSTORMS THROUGH MIDNIGHT. ELSEWHERE...DRY
CONDITIONS WILL PREVAIL INTO MONDAY MORNING. MOZLEY
UPDATE ISSUED AT 550 PM MDT SUN APR 20 2014
ONLY MINOR UPDATES TO THE GOING FORECAST THIS EVENING. AN UPPER
LOW IS SITTING OVER FAR SOUTHWEST KANSAS WITH BROAD NORTHERLY FLOW
ACROSS EASTERN COLORADO. WEAK SHOWER ACTIVITY CONTINUES ACROSS THE
I-25 CORRIDOR AND EASTERN MOUNTAINS WITH ISOLATED THUNDERSTORMS.
STRONGER THUNDERSTORM ACTIVITY IS CURRENTLY SITUATED NEAR THE
UPPER LEVEL DISTURBANCE ALONG THE KANSAS BORDER. LIGHTNING ALONG
WITH 40 MPH OUTFLOW WINDS AND PEA SIZE HAIL ARE ALL POSSIBLE IN
THE STORMS NEAR THE KANSAS BORDER.
MODELS RAPIDLY DISSIPATE SHOWER ACTIVITY AFTER SUNSET WITH ALL
AREAS DRY BY MIDNIGHT. AREAS OUT EAST NEAR THE KANSAS BORDER AND
AREAS DOWN SOUTH ALONG THE NEW MEXICO BORDER WILL HOLD OUT THE
LONGEST. MOZLEY
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 330 PM MDT SUN APR 20 2014
UPPER LOW OVER SE CO/NW NM AND THE TX/OK PANHANDLES WILL CONTINUE
MOVING EAST THIS EVENING. SHOWERS AND THUNDERSTORMS HAVE DEVELOPED
ACROSS SOUTHEAST CO ON THE NORTHWEST SIDE OF THE UPPER LOW IN AREA
OF WEAK ISENTROPIC UPGLIDE AND INSTABILITY. RESIDUAL MOISTURE
ACROSS THE AREA BEHIND THE SYSTEM HAS BEEN SUFFICIENT TO TRIGGER
SOME SCATTERED SHOWERS ACROSS THE MOUNTAINS WITH SOME AFTERNOON
HEATING...AND APPEARS THAT TAIL END OF PASSING SHORTWAVE TO THE
NORTH MAY BE AIDING THUNDERSTORM INITIATION ACROSS NW CO. THIS
LATTER FEATURE WILL CLIP THROUGH NRN CO THIS AFTERNOON AND EVENING.
MAIN CONCERN FOR THE SHORT TERM WILL BE POTENTIAL FOR RUN-OFF
PRODUCING RAINFALL ON THE BURN SCARS. OF GREATER CONCERN WILL BE
THE EAST PEAK BURN SCAR WHERE RAINFALL OCCURRED EARLIER THIS
MORNING. RADAR ESTIMATES COMPARED WITH GAGES IN THE AREA SUGGEST
THAT PORTIONS OF THE BURN SCAR MAY HAVE RECEIVED .50 TO .70 OF
RAINFALL. THIS OCCURRED SLOWLY THOUGH WITH RATES UNDER .10 TO .20
PER HOUR...SO NO PROBLEMS WERE NOTED. HOWEVER IF THIS AREA WERE TO
GET HIT WITH A STRONGER CELL THIS AFTERNOON OR EVENING...THE
SATURATED GROUND MAY RESULT IN SOME QUICK RUN-OFF PROBLEMS.
HOWEVER...CLOUD COVER IN THIS AREA MAY ALSO HELP KEEP THE
ATMOSPHERE MORE STABLE...SO RISK SEEMS LOW AT THIS POINT.
A LITTLE BETTER HEATING HAS BEEN REALIZED FARTHER NORTH ACROSS THE
PIKES PEAK REGION. HOWEVER...DEW POINTS HAVE BEEN DROPPING INTO THE
LOWER 30S AND LATEST HRRR DROPS THEM INTO THE UPPER 20S BY LATE
AFTERNOON WHICH REALLY CUTS BACK ON THE INSTABILITY AND RESULTANT
THUNDERSTORM STRENGTH. WHILE CAN`T ENTIRELY RULE OUT AN ISOLATED
STRONGER CELL IMPACTING THE WALDO CANYON BURN SCAR...THINK THIS
CHANCE IS FAIRLY LOW...AND IF IT DID WOULD PROBABLY NOT LAST LONG
ENOUGH TO PRODUCE MUCH MORE THAN SOME MINOR RUN-OFF ISSUES AT BEST.
ALSO...WATCHING THE SOUTHEAST PLAINS OF THE STATE IN VCNTY OF UPPER
LOW...WHERE LOW LEVEL LAPSE RATES COULD BECOME STEEP ENOUGH TO
PRODUCE A SHORT LIVED NON-SUPERCELL TORNADO/LANDSPOUT. SO
FAR...UPDRAFT STRENGTHS HAVEN`T BEEN STRONG ENOUGH TO STRETCH ANY
LOW LEVEL VORTICITY...BUT WILL CONTINUE TO WATCH IT CLOSELY AS SPC
MESO-ANALYSIS DOES SHOW A POCKET OF HIGH NON-SUPERCELL TOR INDICES
ACROSS PORTIONS OF THE AREA.
ALL ACTIVITY SHIFTS TO THE EAST AND SOUTHEAST FAIRLY QUICKLY THROUGH
LATE AFTERNOON AND EARLY EVENING...SO THESE THREATS SHOULD QUICKLY
COME TO AN END WITH THE LOSS OF HEATING.
ON MONDAY...UPPER RIDGE TRANSLATES IN...BUT THERE WILL STILL BE
ENOUGH RESIDUAL MOISTURE FOR ISOLATED SHOWERS AND THUNDERSTORMS IN
AND NEAR THE MOUNTAINS. OTHERWISE...TEMPERATURES SHOULD BE A LITTLE
WARMER THAN TODAYS...ESPECIALLY IN AND NEAR THE SOUTHEAST MOUNTAINS
WHERE CLOUDS HAVE HELD TEMPERATURES DOWN TODAY. -KT
.LONG TERM...(MONDAY NIGHT THROUGH NEXT SUNDAY)
ISSUED AT 330 PM MDT SUN APR 20 2014
NOT MANY ADJUSTMENTS NEEDED FROM PREVIOUS LONGER TERM THINKING WITH
MAIN LONGER TERM ISSUES BEING ABOVE CLIMATOLOGICAL TEMPERATURES FROM
MONDAY NIGHT INTO EARLY NEXT WEEKEND...ISOLATED TO SCATTERED
POPS...PRIMARILY OVER HIGHER TERRAIN LOCATIONS AT TIMES FROM MONDAY
NIGHT INTO WEDNESDAY AND THEN AGAIN BY NEXT WEEKEND...INCREASING
FIRE WEATHER CONCERNS...BEGINNING WEDNESDAY AFTERNOON AS WELL AS AN
INCREASING POTENTIAL FOR STRONGER TO POSSIBLY SEVERE THUNDERSTORMS
OVER SECTIONS OF THE SOUTHEASTERN COLORADO PLAINS FROM LATER
FRIDAY INTO NEXT WEEKEND.
LATEST LONGER TERM COMPUTER SIMULATIONS AND FORECAST MODEL SOUNDINGS
SUGGEST THAT VARYING DEGREES OF ZONAL TO SOUTHWESTERLY UPPER FLOW
WILL OCCUR OVER THE FORECAST DISTRICT FROM MONDAY NIGHT INTO FRIDAY
MORNING. ISOLATED TO SCATTERED SHOWERS AS WELL AS ISOLATED
THUNDERSTORMS ARE ANTICIPATED OVER PORTIONS OF THE CWFA FROM MONDAY
EVENING INTO WEDNESDAY...FAVORING LOCATIONS SUCH AS THE CENTRAL
MOUNTAINS.
FOCUS THEN SHIFTS TO INCREASING FIRE WEATHER CONCERNS AT
TIMES(ESPECIALLY OVER EASTERN SECTIONS AS WELL AS THE SAN LUIS
VALLEY)...PRIMARILY DURING WEDNESDAY AFTERNOON AND EVENING AND
THEN POSSIBLY CONTINUING AT TIMES INTO EARLY NEXT WEEKEND. WFO
PUEBLO WILL CONTINUE TO MONITOR CLOSELY.
IN ADDITION...METEOROLOGICAL PARAMETERS ARE BEGINNING TO SIGNAL
AN INCREASING POTENTIAL FOR STRONG TO POSSIBLY SEVERE
THUNDERSTORM ACTIVITY OVER PORTIONS OF THE SOUTHEASTERN COLORADO
PLAINS FROM LATER FRIDAY INTO NEXT WEEKEND AS UPPER SYSTEM IMPACTS
THE FORECAST DISTRICT. AS ALWAYS...WFO PUEBLO WILL ALSO CONTINUE
TO MONITOR THESE TRENDS CLOSELY.
SWITCHING FOCUS TO TEMPERATURES...IT STILL APPEARS THAT BOTH MINIMUM
AND MAXIMUM TEMPERATURES WILL RUN ABOVE LATE APRIL CLIMATOLOGICAL
AVERAGES FROM MONDAY NIGHT INTO NEXT SATURDAY BEFORE TEMPERATURES
DECREASE BY NEXT SUNDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 330 PM MDT SUN APR 20 2014
ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS WILL GRADUALLY END
FROM WEST TO EAST THIS EVENING. IFR TO EVEN LOCAL LIFR CIGS/VIS
WILL BE POSSIBLE WITH ANY SHOWERS ACROSS THE MOUNTAINS WHERE WHERE
HEAVY WET SNOW/GRAUPEL AND EVEN SOME SMALL HAIL WILL BE POSSIBLE
WITH THE STRONGER STORMS. CIGS/VIS WILL MORE LIKELY REMAIN VFR
ACROSS THE LOWER ELEVATIONS...THOUGH MVFR TO LOCAL IFR WILL BE
POSSIBLE WITH ANY OF THE STRONGER STORMS ACROSS THE PLAINS. THESE
WILL ALSO CARRY THE THREAT OF SOME SMALL HAIL. CLEARING SKIES WILL
SET IN AFTER SUNSET. VFR CONDITIONS WILL CONTINUE FOR MONDAY WITH
SOME ISOLATED SHOWERS AND THUNDERSTORMS.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...MOZLEY
AREA FORECAST DISCUSSION
NWS PUEBLO CO
553 PM MDT SUN APR 20 2014
.UPDATE...
ISSUED AT 550 PM MDT SUN APR 20 2014
ONLY MINOR UPDATES TO THE GOING FORECAST THIS EVENING. AN UPPER
LOW IS SITTING OVER FAR SOUTHWEST KANSAS WITH BROAD NORTHERLY FLOW
ACROSS EASTERN COLORADO. WEAK SHOWER ACTIVITY CONTINUES ACROSS THE
I-25 CORRIDOR AND EASTERN MOUNTAINS WITH ISOLATED THUNDERSTORMS.
STRONGER THUNDERSTORM ACTIVITY IS CURRENTLY SITUATED NEAR THE
UPPER LEVEL DISTURBANCE ALONG THE KANSAS BORDER. LIGHTNING ALONG
WITH 40 MPH OUTFLOW WINDS AND PEA SIZE HAIL ARE ALL POSSIBLE IN
THE STORMS NEAR THE KANSAS BORDER.
MODELS RAPIDLY DISSIPATE SHOWER ACTIVITY AFTER SUNSET WITH ALL
AREAS DRY BY MIDNIGHT. AREAS OUT EAST NEAR THE KANSAS BORDER AND
AREAS DOWN SOUTH ALONG THE NEW MEXICO BORDER WILL HOLD OUT THE
LONGEST. MOZLEY
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 330 PM MDT SUN APR 20 2014
UPPER LOW OVER SE CO/NW NM AND THE TX/OK PANHANDLES WILL CONTINUE
MOVING EAST THIS EVENING. SHOWERS AND THUNDERSTORMS HAVE DEVELOPED
ACROSS SOUTHEAST CO ON THE NORTHWEST SIDE OF THE UPPER LOW IN AREA
OF WEAK ISENTROPIC UPGLIDE AND INSTABILITY. RESIDUAL MOISTURE
ACROSS THE AREA BEHIND THE SYSTEM HAS BEEN SUFFICIENT TO TRIGGER
SOME SCATTERED SHOWERS ACROSS THE MOUNTAINS WITH SOME AFTERNOON
HEATING...AND APPEARS THAT TAIL END OF PASSING SHORTWAVE TO THE
NORTH MAY BE AIDING THUNDERSTORM INITIATION ACROSS NW CO. THIS
LATTER FEATURE WILL CLIP THROUGH NRN CO THIS AFTERNOON AND EVENING.
MAIN CONCERN FOR THE SHORT TERM WILL BE POTENTIAL FOR RUN-OFF
PRODUCING RAINFALL ON THE BURN SCARS. OF GREATER CONCERN WILL BE
THE EAST PEAK BURN SCAR WHERE RAINFALL OCCURRED EARLIER THIS
MORNING. RADAR ESTIMATES COMPARED WITH GAGES IN THE AREA SUGGEST
THAT PORTIONS OF THE BURN SCAR MAY HAVE RECEIVED .50 TO .70 OF
RAINFALL. THIS OCCURRED SLOWLY THOUGH WITH RATES UNDER .10 TO .20
PER HOUR...SO NO PROBLEMS WERE NOTED. HOWEVER IF THIS AREA WERE TO
GET HIT WITH A STRONGER CELL THIS AFTERNOON OR EVENING...THE
SATURATED GROUND MAY RESULT IN SOME QUICK RUN-OFF PROBLEMS.
HOWEVER...CLOUD COVER IN THIS AREA MAY ALSO HELP KEEP THE
ATMOSPHERE MORE STABLE...SO RISK SEEMS LOW AT THIS POINT.
A LITTLE BETTER HEATING HAS BEEN REALIZED FARTHER NORTH ACROSS THE
PIKES PEAK REGION. HOWEVER...DEW POINTS HAVE BEEN DROPPING INTO THE
LOWER 30S AND LATEST HRRR DROPS THEM INTO THE UPPER 20S BY LATE
AFTERNOON WHICH REALLY CUTS BACK ON THE INSTABILITY AND RESULTANT
THUNDERSTORM STRENGTH. WHILE CAN`T ENTIRELY RULE OUT AN ISOLATED
STRONGER CELL IMPACTING THE WALDO CANYON BURN SCAR...THINK THIS
CHANCE IS FAIRLY LOW...AND IF IT DID WOULD PROBABLY NOT LAST LONG
ENOUGH TO PRODUCE MUCH MORE THAN SOME MINOR RUN-OFF ISSUES AT BEST.
ALSO...WATCHING THE SOUTHEAST PLAINS OF THE STATE IN VCNTY OF UPPER
LOW...WHERE LOW LEVEL LAPSE RATES COULD BECOME STEEP ENOUGH TO
PRODUCE A SHORT LIVED NON-SUPERCELL TORNADO/LANDSPOUT. SO
FAR...UPDRAFT STRENGTHS HAVEN`T BEEN STRONG ENOUGH TO STRETCH ANY
LOW LEVEL VORTICITY...BUT WILL CONTINUE TO WATCH IT CLOSELY AS SPC
MESO-ANALYSIS DOES SHOW A POCKET OF HIGH NON-SUPERCELL TOR INDICES
ACROSS PORTIONS OF THE AREA.
ALL ACTIVITY SHIFTS TO THE EAST AND SOUTHEAST FAIRLY QUICKLY THROUGH
LATE AFTERNOON AND EARLY EVENING...SO THESE THREATS SHOULD QUICKLY
COME TO AN END WITH THE LOSS OF HEATING.
ON MONDAY...UPPER RIDGE TRANSLATES IN...BUT THERE WILL STILL BE
ENOUGH RESIDUAL MOISTURE FOR ISOLATED SHOWERS AND THUNDERSTORMS IN
AND NEAR THE MOUNTAINS. OTHERWISE...TEMPERATURES SHOULD BE A LITTLE
WARMER THAN TODAYS...ESPECIALLY IN AND NEAR THE SOUTHEAST MOUNTAINS
WHERE CLOUDS HAVE HELD TEMPERATURES DOWN TODAY. -KT
.LONG TERM...(MONDAY NIGHT THROUGH NEXT SUNDAY)
ISSUED AT 330 PM MDT SUN APR 20 2014
NOT MANY ADJUSTMENTS NEEDED FROM PREVIOUS LONGER TERM THINKING WITH
MAIN LONGER TERM ISSUES BEING ABOVE CLIMATOLOGICAL TEMPERATURES FROM
MONDAY NIGHT INTO EARLY NEXT WEEKEND...ISOLATED TO SCATTERED
POPS...PRIMARILY OVER HIGHER TERRAIN LOCATIONS AT TIMES FROM MONDAY
NIGHT INTO WEDNESDAY AND THEN AGAIN BY NEXT WEEKEND...INCREASING
FIRE WEATHER CONCERNS...BEGINNING WEDNESDAY AFTERNOON AS WELL AS AN
INCREASING POTENTIAL FOR STRONGER TO POSSIBLY SEVERE THUNDERSTORMS
OVER SECTIONS OF THE SOUTHEASTERN COLORADO PLAINS FROM LATER
FRIDAY INTO NEXT WEEKEND.
LATEST LONGER TERM COMPUTER SIMULATIONS AND FORECAST MODEL SOUNDINGS
SUGGEST THAT VARYING DEGREES OF ZONAL TO SOUTHWESTERLY UPPER FLOW
WILL OCCUR OVER THE FORECAST DISTRICT FROM MONDAY NIGHT INTO FRIDAY
MORNING. ISOLATED TO SCATTERED SHOWERS AS WELL AS ISOLATED
THUNDERSTORMS ARE ANTICIPATED OVER PORTIONS OF THE CWFA FROM MONDAY
EVENING INTO WEDNESDAY...FAVORING LOCATIONS SUCH AS THE CENTRAL
MOUNTAINS.
FOCUS THEN SHIFTS TO INCREASING FIRE WEATHER CONCERNS AT
TIMES(ESPECIALLY OVER EASTERN SECTIONS AS WELL AS THE SAN LUIS
VALLEY)...PRIMARILY DURING WEDNESDAY AFTERNOON AND EVENING AND
THEN POSSIBLY CONTINUING AT TIMES INTO EARLY NEXT WEEKEND. WFO
PUEBLO WILL CONTINUE TO MONITOR CLOSELY.
IN ADDITION...METEOROLOGICAL PARAMETERS ARE BEGINNING TO SIGNAL
AN INCREASING POTENTIAL FOR STRONG TO POSSIBLY SEVERE
THUNDERSTORM ACTIVITY OVER PORTIONS OF THE SOUTHEASTERN COLORADO
PLAINS FROM LATER FRIDAY INTO NEXT WEEKEND AS UPPER SYSTEM IMPACTS
THE FORECAST DISTRICT. AS ALWAYS...WFO PUEBLO WILL ALSO CONTINUE
TO MONITOR THESE TRENDS CLOSELY.
SWITCHING FOCUS TO TEMPERATURES...IT STILL APPEARS THAT BOTH MINIMUM
AND MAXIMUM TEMPERATURES WILL RUN ABOVE LATE APRIL CLIMATOLOGICAL
AVERAGES FROM MONDAY NIGHT INTO NEXT SATURDAY BEFORE TEMPERATURES
DECREASE BY NEXT SUNDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 330 PM MDT SUN APR 20 2014
ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS WILL GRADUALLY END
FROM WEST TO EAST THIS EVENING. IFR TO EVEN LOCAL LIFR CIGS/VIS
WILL BE POSSIBLE WITH ANY SHOWERS ACROSS THE MOUNTAINS WHERE WHERE
HEAVY WET SNOW/GRAUPEL AND EVEN SOME SMALL HAIL WILL BE POSSIBLE
WITH THE STRONGER STORMS. CIGS/VIS WILL MORE LIKELY REMAIN VFR
ACROSS THE LOWER ELEVATIONS...THOUGH MVFR TO LOCAL IFR WILL BE
POSSIBLE WITH ANY OF THE STRONGER STORMS ACROSS THE PLAINS. THESE
WILL ALSO CARRY THE THREAT OF SOME SMALL HAIL. CLEARING SKIES WILL
SET IN AFTER SUNSET. VFR CONDITIONS WILL CONTINUE FOR MONDAY WITH
SOME ISOLATED SHOWERS AND THUNDERSTORMS.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...MOZLEY
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
1011 AM MDT SAT APR 19 2014
.UPDATE...
ISSUED AT 1011 AM MDT SAT APR 19 2014
FORECAST LOOKS GOOD WITH MOSTLY CLOUDY...COOLER...AND INCREASE IN
SHOWERS THIS AFTERNOON. COLD FRONT HAD PUSHED ACROSS MOST OF THE
FORECAST AREA INCLUDING DENVER THIS MORNING. MEANWHILE...A THICK
MID/UPPER LEVEL CLOUD DECK REMAINED ACROSS THE FORECAST AREA. THIS
CLOUD DECK WAS SHOWING SOME SIGNS OF THINNING IN THE LATEST
SATELLITE PICS...SO WE SHOULD SEE A FEW BREAKS THROUGH EARLY
AFTERNOON BEFORE CONVECTIVE CLOUDINESS AND NEARLY OVERCAST SKIES
REDEVELOP LATER THIS AFTERNOON. THE MOST NUMEROUS SHOWERS ARE
EXPECTED TO DEVELOP IN THE PARK/SUMMIT COUNTY AREA STRETCHING
NORTHWARD ALONG THE FRONT RANGE FOOTHILLS WHERE BEST BUT STILL
WEAK INSTABILITY IS PROGGED. CAPES ONLY ABOUT 100-300 J/KG BUT
SHOULD STILL BE ENOUGH FOR THUNDER AND BRIEF HEAVY RAIN...SNOW IN
ELEVATIONS ABOVE 10-10.5 THOUSAND FEET. DID INCREASE
POPS...QPF...AND HIGHER ELEVATIONS SNOW AMOUNTS A BIT MORE IN
THOSE LOCATIONS. I-25 URBAN CORRIDOR ON THE EDGE OF ANY
INSTABILITY BUT SHOULD STILL SEE SCATTERED SHOWERS AND PERHAPS AN
ISOLATED STORM DRIFT OFF THE HIGHER TERRAIN. EASTERN PLAINS LOOK
TOO STABLE BEHIND WEAK FRONTAL PASSAGE FOR MUCH CONVECTION UNTIL
PERHAPS LATER IN THE AFTERNOON SO DELAYED WEATHER CHANCES
THERE...AND EVEN THOSE ARE QUITE SMALL.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT )
ISSUED AT 410 AM MDT SAT APR 19 2014
MID- AND HIGH-LEVEL MOISTURE CONTINUES TO FLOW IN FROM THE DESERT
SOUTHWEST IN ADVANCE OF A CLOSED LOW OVER SOUTHERN CALIFORNIA AND
UPPER LEVEL OPEN WAVE TROUGH SLOWLY PROGRESSING EASTWARD ACROSS
THE REGION. IR SAT IMAGERY HAS SHOWN A DRAMATIC INCREASE IN
MID/HIGH CLOUD COVER OVER EASTERN COLORADO IN THE PAST HOUR IN
RESPONSE TO THIS INFLUX OF MOISTURE AND WARM SECTOR ISENTROPIC
LIFT. NOT SEEING ANY PRECIP REACHING THE GROUND AS OF YET...
EXCEPT PERHAPS ON THE HIGH MTN PEAKS. MEANWHILE A SFC TROUGH IN
ERN COLORADO INTERSECTS WITH A RELATIVELY WEAK SFC COLD FRONT
ADVANCING SEWRD ACROSS NRN WYOMING AND NORTHWEST NEBRASKA AT THIS
TIME. TEMPERATURE...THICKNESS AND WIND FIELDS SHOW THIS NEBULOUS
FRONTAL BOUNDARY REACHING THE NORTHEAST CORNER OF COLORADO JUST
BEFORE 1200Z AND MOVING INTO THE DENVER METRO AREA AROUND 1500Z.
AIR ONLY SLIGHTLY COOLER AND MORE HUMID BEHIND THIS BNDRY. POCKETS
OF GUSTY NELY WINDS CAN BE SEEN JUST BEHIND THIS FRONT. WITH THE
MAIN RISE/FALL PRESSURE COUPLET REMAINING WELL EAST OF THE
CWA...MODELS SHOW POST-FRONTAL WINDS WEAKENING AS THEY MAKE THEIR
WAY TO THE FRONT RANGE. HOWEVER MAY STILL SEE A SHORT PERIOD OF
15-20KT NELY WINDS WITH FRONTAL PASSAGE. WITH POST FRONTAL UPSLOPE
FLOW IN PLACE SHOULD SEE A STEADY LOWERING OF CLOUD BASES ALONG
AND EAST OF THE FRONT RANGE AS THE BOUNDARY LAYER CONTINUES TO
MOISTEN. IN ADDITION...THE PASSAGE OF A WEAK VORT LOBE NOW
CROSSING SWRN COLORADO WILL PROVIDE ADDITIONAL LIFT AND MOISTURE
FOR FAIRLY RAPID SHOWER FORMATION IN THE CENTRAL MTNS AROUND SOUTH
PARK LATER THIS MORNING. MODELS INDICATE THIS HAPPENING AFTER
1500Z.
SHOULD SEE SYNOPTIC SCALE LIFT AND INSTABILITY INCREASE THROUGH THE
DAY OVER THE CWA WITH THE UPPER TROUGH INCHING CLOSER. WRF...NAM
AND HRRR SHOW SCATTERED CONVECTION OVER THE FRONT RANGE DRIFTING
OVER THE I-25 URBAN CORRIDOR AFTER 2000Z TODAY. MODEL
REFLECTIVITIES ARE GENERALLY OF LOW INTENSITY. ALTHOUGH THE WRF
AND NAM SHOW A BAND OF 20-35DBZ CELLS SWINGING SEWRD ACROSS THE
DENVER METRO AREA JUST PRIOR TO 20/0000Z AND THEN OVER DOUGLAS AND
WESTERN ELBERT COUNTIES BETWEEN 0000Z AND 0300Z. MODELS SHOW A
FAIRLY DEEP EASTERLY LOW-LEVEL FLOW SETTING UP ALONG THE SPINE OF
THE PALMER DIVIDE THIS AFTERNOON WHICH DRIVES A THETA-E RIDGE UP
AGAINST THE SOUTHERN FOOTHILLS. THIS IS WHERE THE POTENTIAL FOR
BRIEF HEAVY RAINFALL WILL EXIST LATE THIS AFTERNOON AND EVENING.
COULD SEE UPWARDS OF A HALF INCH OF RAIN IN A SHORT PERIOD WITH
ISOLATED STORM CELLS ALONG THIS AXIS. GUSTY OUTFLOW WINDS ALSO
POSSIBLE. NOT AS CONFIDENT WE/LL SEE ANY HAIL FROM THESE LOW-TOP
T-STORMS AS CAPES AND LAPSE RATES NOT AS IMPRESSIVE AS MODELS
INDICATED YESTERDAY. ELSEWHERE...LOW POPS WARRANTED UNDER MOSTLY
CLOUDY TO OVERCAST SKIES. TEMPERATURES TODAY AS MUCH AS 15 DEG F
COOLER THAN YESTERDAY.
SHOWER ACTIVITY APPEARS TO QUICKLY DROP OFF FROM NORTH TO SOUTH THIS
EVENING. ALTHOUGH...A SMATTERING OF WEAK SHOWERS MAY LINGER OVER THE
HIGH TERRAIN SOUTHWEST OF DENVER AND ACROSS SOUTH PARK THROUGH THE
WEE HOURS OF THE MORNING. OVERNIGHT...TEMPERATURES WILL LOW ENOUGH
FOR A RAIN/SNOW MIX IN THIS AREA. IT IS POSSIBLE THE SOUTHERN
FOOTHILLS COULD SEE AN INCH OR TWO OF WET SNOW BEFORE MIDNIGHT.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 410 AM MDT SAT APR 19 2014
ON SUNDAY...THE UPPER LEVEL TROF WILL SLOWLY SHIFT EASTWARD INTO
THE CENTRAL PLAINS WITH MOST OF THE MOISTURE AND ENERGY ACROSS
SOUTHEAST PORTION OF CWA. THIS ALREADY REFLECTED IN FORECAST WITH
LITTLE CHANGE NEEDED. DRIER FURTHER NORTH BUT ENOUGH MOISTURE AND
INSTABLITY FOR SCATTERED SHOWER COVERAGE IN THE MOUNTAINS.
HIGH PRESSURE RIDGE BUILDS IN ALOFT OVER COLORADO AS FLOW ALOFT
SHIFTS MORE NORTHWEST ON MONDAY. A COLD FRONT PUSHES ACROSS
NORTHEAST COLORADO SUNDAY NIGHT WITH SLIGHTLY COOLER TEMPERATURES
ON MONDAY. DRY AND MORE STABLE ON THE PLAINS BEHIND THE FRONT BUT
THERE WILL BE SOME SHOWERS AND STORMS OVER MOUNTAINS AND EAST
SLOPES AS LIGHT SOUTHEAST FLOW POOLS MOISTURE OVER EAST SLOPES.
FOR TUESDAY AND EARLY WEDNESDAY NEXT TROF DEEPENS OVER THE
NORTHERN GREAT BASIN WITH INCREASING SOUTHWEST FLOW ALOFT. THIS
WILL RESULT IN BIG WARMUP OVER LOWER ELEVATIONS AS STRONG
SOUTHERLY FLOW DEVELOPS OVER THE PLAINS. COULD BE A DRY LINE SETUP
OVER THE EASTERN BORDER WITH KANSAS WITH HIGHER DEWPOINTS IN THE
40S. BEST CHANCES FOR STORMS WILL BE OVER THE FAR PLAINS WITH
BETTER LOW LEVEL MOISTURE. FURTHER WEST TOWARDS THE FRONT
RANGE...GENERALLY DRY SOUTHWEST FLOW. THE UPPER TROF LIFTS
NORTHEAST INTO THE NORTHERN ROCKY MOUNTAIN REGION AND HIGH PLAINS
LATE WEDNESDAY AND THURSDAY. THIS WILL RESULT IN DRY...COOLER AND
WINDY CONDITIONS ON THE NORTHEAST PLAINS.
HIGH PRESSURE ALOFT WILL BUILD AGAIN INTO COLORADO ON FRIDAY FOR
GENERALLY DRY CONDITIONS AND WARMER TEMPERATURES AGAIN.
&&
.AVIATION...(FOR THE TAFS THROUGH 00Z SUNDAY AFTERNOON)
ISSUED AT 1011 AM MDT SAT APR 19 2014
WEAK COLD FRONT HAS PUSHED ACROSS THE FRONT RANGE AIRPORTS WITH
WINDS BECOMING MORE EAST/NORTHEASTERLY. WINDS SPEEDS ALREADY
SLACKING OFF TO 10 KTS OR LESS BEHIND THE FRONT AND TURNING MORE
EASTERLY. EXPECT WINDS TO REMAIN THIS WAY THROUGH THE AFTERNOON
UNTIL SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS MAY DEVELOP AFT
21Z WITH VARIABLE WIND GUSTS 15-25 KTS NEAR SHOWERS. CEILINGS
COULD LOWER TO AROUND 6 THOUSAND FEET FOR ILS LANDING CONDITIONS
WITH ANY PASSING SHOWERS 21Z-02Z. OTHERWISE VISUAL LANDINGS
WILL PREVAIL. CHANCE OF ANY THUNDER IS QUITE LOW WITH CAPES LESS
THAN 100 J/KG.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...BARJENBRUCH
SHORT TERM...BAKER
LONG TERM...ENTREKIN
AVIATION...BARJENBRUCH
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
410 AM MDT SAT APR 19 2014
.SHORT TERM...(TODAY THROUGH TONIGHT )
ISSUED AT 244 AM MDT SAT APR 19 2014
MID- AND HIGH-LEVEL MOISTURE CONTINUES TO FLOW IN FROM
THE DESERT SOUTHWEST IN ADVANCE OF A CLOSED LOW OVER SOUTHERN
CALIFORNIA AND UPPER LEVEL OPEN WAVE TROUGH SLOWLY PROGRESSING
EASTWARD ACROSS THE REGION. IR SAT IMAGERY HAS SHOWN A DRAMATIC
INCREASE IN MID/HIGH CLOUD COVER OVER EASTERN COLORADO IN THE
PAST HOUR IN RESPONSE TO THIS INFLUX OF MOISTURE AND WARM SECTOR
ISENTROPIC LIFT. NOT SEEING ANY PRECIP REACHING THE GROUND AS OF
YET... EXCEPT PERHAPS ON THE HIGH MTN PEAKS. MEANWHILE A SFC
TROUGH IN ERN COLORADO INTERSECTS WITH A RELATIVELY WEAK SFC COLD
FRONT ADVANCING SEWRD ACROSS NRN WYOMING AND NORTHWEST NEBRASKA AT
THIS TIME. TEMPERATURE...THICKNESS AND WIND FIELDS SHOW THIS
NEBULOUS FRONTAL BOUNDARY REACHING THE NORTHEAST CORNER OF
COLORADO JUST BEFORE 1200Z AND MOVING INTO THE DENVER METRO AREA
AROUND 1500Z. AIR ONLY SLIGHTLY COOLER AND MORE HUMID BEHIND THIS
BNDRY. POCKETS OF GUSTY NELY WINDS CAN BE SEEN JUST BEHIND THIS
FRONT. WITH THE MAIN RISE/FALL PRESSURE COUPLET REMAINING WELL
EAST OF THE CWA...MODELS SHOW POST-FRONTAL WINDS WEAKENING AS THEY
MAKE THEIR WAY TO THE FRONT RANGE. HOWEVER MAY STILL SEE A SHORT
PERIOD OF 15-20KT NELY WINDS WITH FRONTAL PASSAGE. WITH POST
FRONTAL UPSLOPE FLOW IN PLACE SHOULD SEE A STEADY LOWERING OF
CLOUD BASES ALONG AND EAST OF THE FRONT RANGE AS THE BOUNDARY
LAYER CONTINUES TO MOISTEN. IN ADDITION...THE PASSAGE OF A WEAK
VORT LOBE NOW CROSSING SWRN COLORADO WILL PROVIDE ADDITIONAL LIFT
AND MOISTURE FOR FAIRLY RAPID SHOWER FORMATION IN THE CENTRAL MTNS
AROUND SOUTH PARK LATER THIS MORNING. MODELS INDICATE THIS
HAPPENING AFTER 1500Z.
SHOULD SEE SYNOPTIC SCALE LIFT AND INSTABILITY INCREASE THROUGH THE
DAY OVER THE CWA WITH THE UPPER TROUGH INCHING CLOSER. WRF...NAM
AND HRRR SHOW SCATTERED CONVECTION OVER THE FRONT RANGE DRIFTING
OVER THE I-25 URBAN CORRIDOR AFTER 2000Z TODAY. MODEL
REFLECTIVITIES ARE GENERALLY OF LOW INTENSITY. ALTHOUGH THE WRF
AND NAM SHOW A BAND OF 20-35DBZ CELLS SWINGING SEWRD ACROSS THE
DENVER METRO AREA JUST PRIOR TO 20/0000Z AND THEN OVER DOUGLAS AND
WESTERN ELBERT COUNTIES BETWEEN 0000Z AND 0300Z. MODELS SHOW A
FAIRLY DEEP EASTERLY LOW-LEVEL FLOW SETTING UP ALONG THE SPINE OF
THE PALMER DIVIDE THIS AFTERNOON WHICH DRIVES A THETA-E RIDGE UP
AGAINST THE SOUTHERN FOOTHILLS. THIS IS WHERE THE POTENTIAL FOR
BRIEF HEAVY RAINFALL WILL EXIST LATE THIS AFTERNOON AND EVENING.
COULD SEE UPWARDS OF A HALF INCH OF RAIN IN A SHORT PERIOD WITH
ISOLATED STORM CELLS ALONG THIS AXIS. GUSTY OUTFLOW WINDS ALSO
POSSIBLE. NOT AS CONFIDENT WE/LL SEE ANY HAIL FROM THESE LOW-TOP
T-STORMS AS CAPES AND LAPSE RATES NOT AS IMPRESSIVE AS MODELS
INDICATED YESTERDAY. ELSEWHERE...LOW POPS WARRANTED UNDER MOSTLY
CLOUDY TO OVERCAST SKIES. TEMPERATURES TODAY AS MUCH AS 15 DEG F
COOLER THAN YESTERDAY.
SHOWER ACTIVITY APPEARS TO QUICKLY DROP OFF FROM NORTH TO SOUTH THIS
EVENING. ALTHOUGH...A SMATTERING OF WEAK SHOWERS MAY LINGER OVER THE
HIGH TERRAIN SOUTHWEST OF DENVER AND ACROSS SOUTH PARK THROUGH THE
WEE HOURS OF THE MORNING. OVERNIGHT...TEMPERATURES WILL LOW ENOUGH
FOR A RAIN/SNOW MIX IN THIS AREA. IT IS POSSIBLE THE SOUTHERN
FOOTHILLS COULD SEE AN INCH OR TWO OF WET SNOW BEFORE MIDNIGHT.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 244 AM MDT SAT APR 19 2014
ON SUNDAY...THE UPPER LEVEL TROF WILL SLOWLY SHIFT EASTWARD INTO
THE CENTRAL PLAINS WITH MOST OF THE MOISTURE AND ENERGY ACROSS
SOUTHEAST PORTION OF CWA. THIS ALREADY REFLECTED IN FORECAST WITH
LITTLE CHANGE NEEDED. DRIER FURTHER NORTH BUT ENOUGH MOISTURE AND
INSTABLITY FOR SCATTERED SHOWER COVERAGE IN THE MOUNTAINS.
HIGH PRESSURE RIDGE BUILDS IN ALOFT OVER COLORADO AS FLOW ALOFT
SHIFTS MORE NORTHWEST ON MONDAY. A COLD FRONT PUSHES ACROSS
NORTHEAST COLORADO SUNDAY NIGHT WITH SLIGHTLY COOLER TEMPERATURES
ON MONDAY. DRY AND MORE STABLE ON THE PLAINS BEHIND THE FRONT BUT
THERE WILL BE SOME SHOWERS AND STORMS OVER MOUNTAINS AND EAST
SLOPES AS LIGHT SOUTHEAST FLOW POOLS MOISTURE OVER EAST SLOPES.
FOR TUESDAY AND EARLY WEDNESDAY NEXT TROF DEEPENS OVER THE
NORTHERN GREAT BASIN WITH INCREASING SOUTHWEST FLOW ALOFT. THIS
WILL RESULT IN BIG WARMUP OVER LOWER ELEVATIONS AS STRONG
SOUTHERLY FLOW DEVELOPS OVER THE PLAINS. COULD BE A DRY LINE SETUP
OVER THE EASTERN BORDER WITH KANSAS WITH HIGHER DEWPOINTS IN THE
40S. BEST CHANCES FOR STORMS WILL BE OVER THE FAR PLAINS WITH
BETTER LOW LEVEL MOISTURE. FURTHER WEST TOWARDS THE FRONT
RANGE...GENERALLY DRY SOUTHWEST FLOW. THE UPPER TROF LIFTS
NORTHEAST INTO THE NORTHERN ROCKY MOUNTAIN REGION AND HIGH PLAINS
LATE WEDNESDAY AND THURSDAY. THIS WILL RESULT IN DRY...COOLER AND
WINDY CONDITIONS ON THE NORTHEAST PLAINS.
HIGH PRESSURE ALOFT WILL BUILD AGAIN INTO COLORADO ON FRIDAY FOR
GENERALLY DRY CONDITIONS AND WARMER TEMPERATURES AGAIN.
&&
.AVIATION...(FOR THE TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 244 AM MDT SAT APR 19 2014
COLD FRONT IS EXPECTED TO MOVE TROUGH THE DENVER AREA FROM THE
NORTHEAST AROUND 1500Z THIS MORNING. WINDS WILL SHIFT FROM WEST-
NORTHWEST TO A NORTHEAST COMPONENT WITH ITS PASSAGE. COULD SEE A
1-2 HOUR PERIOD OF 15-20 KTS GUSTS WITH FROPA. CLOUD BASES WILL
LOWER THROUGH THE DAY WITH BASES AS LOW AS 5000-6000 FEET AGL WITH
SCATTERED SHOWERS AND ISOLATED T-STORMS THIS AFTERNOON. BEST
CHANCE FOR THESE SHOWERS IN THE DENVER AREA BETWEEN 19/2100Z AND
20/0100Z. OVERNIGHT...SHOULD SEE A GRADUAL RISE IN CLOUD BASES
WITH PARTIAL CLEARING AFTER MIDNIGHT. EXPECT EAST-NORTHEAST SFC
WINDS OF 8-15KTS IN THE AFTERNOON...SOUTHEAST WINDS OF 7-12KTS IN
THE EVENING...THEN LIGHT DRAINAGE FLOW AFTER MIDNIGHT.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BAKER
LONG TERM...ENTREKIN
AVIATION...BAKER
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
1045 PM MDT FRI APR 18 2014
.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 336 PM MDT FRI APR 18 2014
WINDS HAVE PICKED UP THIS AFTERNOON AS EXPECTED AND WILL CONTINUE
TO BE INCREASED PAST SUNSET AS A WEATHER DISTURBANCE APPROACHES
FROM THE SOUTHWEST. THE MAIN ACTIVITY FROM THIS SYSTEM IS
CURRENTLY AFFECTING SOUTHERN ARIZONA AND HEADING NORTH TOWARD THE
FOUR CORNERS. THE SHORT TERM RAP AND NAM MODELS HAVE DONE WELL IN
FORECASTING THE ISOLATED SHOWERS THIS AFTERNOON AFTER THE NORTHERN
SAN JUAN AND ELK MOUNTAINS. THE POSSIBILITY OF ISOLATED SHOWERS
AND A POSSIBLE STRIKE OF LIGHTNING WILL CONTINUE THROUGH MIDNIGHT.
MODEL SKEW-TS ACROSS SOUTHWESTERN COLORADO ARE SHOWING A CLASSIC
`V` PATTERN WHICH SUGGESTS STRONG OUTFLOW WINDS TONIGHT FROM VIRGA
AND SHOWERS WHICH DO DEVELOP.
JUST AFTER MIDNIGHT...A SURGE OF MOISTURE FROM THE SOUTHWEST IS
EXPECTED TO REACH THE FOUR CORNERS AND CONTINUE NORTHEAST.
SCATTERED TO NUMEROUS SHOWERS ARE EXPECTED WITH POSSIBLE EMBEDDED
THUNDERSTORMS. LOOKS LIKE THERE WILL BE AN AREA OF RAIN/SNOW WITH
SNOW LEVEL STARTING NEAR 8500 FT OVERNIGHT MOVING NORTHEAST AND
TAPERING OFF IN COVERAGE AS IT PASSES OVER THE SOUTHWESTERN CO
MTNS. HOWEVER...WITH PWATS WELL ABOVE NORMAL AT 0.50 TO 0.70 INCH
BY NOON SATURDAY...EXPECTING SCATTERED TO NUMEROUS SHOWERS ACROSS
THE CWA SATURDAY AFTERNOON WITH ISOLATED/SCATTERED THUNDERSTORMS
AS WELL. WITH SO MUCH POTENTIAL PRECIPITATION...STORMS THAT DO
DEVELOP COULD PACK A GOOD PUNCH OF WATER. SNOW LEVEL WILL RISE TO
NEAR 10000 FEET BY NOON SO THE WINTER SNOWPACK IS EXPECTED TO
DIMINISH...THEREFORE SMALL STREAMS AND CREEKS COULD RISE QUICKLY.
USE CAUTION IF TRAVELING THROUGH THE BACKCOUNTRY OR TRAVELING NEAR
LOW-LYING AREAS ALONG SMALL DRAINAGES. WE APPRECIATE ANY REPORTS
OF RISING WATER.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 336 PM MDT FRI APR 18 2014
LINGERING MOISTURE BEHIND SATURDAY/S DISTURBANCE WILL ALLOW ISOLATED
TO SCATTERED SHOWERS AND THUNDERSTORMS TO DEVELOP OVER THE MOUNTAINS
DURING THE AFTERNOON. HELPING THIS CONVECTION WILL BE A WEAK WAVE
PASSING TO OUR NORTH...AND DAYTIME SURFACE HEATING. WHILE A FEW
MOUNTAIN SHOWERS WILL AGAIN BE POSSIBLE MONDAY AFTERNOON A DOWNTURN
IS EXPECTED AS A RIDGE PASSES OVERHEAD...AND THE NEXT LOW PRESSURE
TROUGH APPROACHES THE PACIFIC NORTHWEST COAST.
MODELS INDICATE THE POTENTIAL FOR A SIGNIFICANT WIND EVENT ON
TUESDAY AS THIS TROUGH SHIFTS INLAND AND INTO THE GREAT BASIN. ALSO
AN ASSOCIATED COLD FRONT WILL APPROACH OUR FORECAST AREA FROM THE
NORTHWEST LATE TUE-TUE NIGHT. WARMING AHEAD OF THE FRONT...AND THE
TIGHTENING GRADIENT WILL PRODUCE WARM...WINDY AND DRY CONDITIONS.
MODELS DO SHOW SOME SOME MID-HIGH LEVEL MOISTURE WHICH MAY ACT TO
DAMPEN THE WINDS. HOWEVER MODEL SOUNDINGS SHOW AN INVERTED-V
SIGNATURE...FOR THE POTENTIAL OF VIRGA OR LIGHT HIGH-BASED SHOWERS
WHICH WOULD GREATLY BOOST WIND GUSTS. AT THIS TIME...IT LOOKS LIKE
THE COLD FRONT WILL PUSH INTO THE NORTHWEST CORNER AROUND MIDNIGHT
TUE NIGHT...THEN ACROSS MOST OF THE FORECAST AREA BY LATE WED
MORNING. THIS WILL KEEP THE AIR MASS UNSETTLED THROUGH THE
NIGHT...WITH STRONG WIND GUSTS AGAIN DEVELOPING ALONG THE FAR
SOUTHERN BORDER WED MORNING AND EARLY AFTERNOON. SINCE THE BULK OF
THE UPPER LEVEL SYSTEM AND THE ASSOCIATED MOISTURE WILL REMAIN TO
OUR NORTH...THIS WILL NOT BE A BIG PRECIPITATION PRODUCER FOR OUR
AREA. A CHANCE OF SHOWERS WILL DEVELOP OVER THE NORTHERN PORTION ON
WEDNESDAY BEHIND THE FRONT...ONLY ISOLATED MOUNTAIN SHOWERS ARE
EXPECTED IN THE SOUTH.
THEN WITH PRETTY GOOD AGREEMENT...THE 12Z MODEL RUNS INDICATE A
RIDGE BUILDING OVER THE REGION FOR THU AND FRI.
AFTER WARMING CONDITIONS EARLY IN THE WEEK...ESPECIALLY ON
TUESDAY...TEMPERATURES COULD DROP BY 15 OR MORE DEGREES ON WEDNESDAY
AND THURSDAY BEHIND THE FRONT. TEMPS THEN WARM AGAIN ON FRIDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1045 PM MDT FRI APR 18 2014
WESTERN COLORADO AND EASTERN UTAH WILL BE STUCK BETWEEN SYSTEMS
PASSING THROUGH THE NORTHERN HIGH PLAINS AND LIFTING ACROSS
ARIZONA AND NEW MEXICO THE NEXT 24 HOURS. CURRENTLY MOISTURE IS
STREAMING NORTHWARD...MAINLY IN THE FORM OF MID AND HIGH
CLOUDINESS. DRY AIR NEAR THE SURFACE IS PREVENTING MOISTURE FROM
GETTING INTO THE VALLEYS. GUSTY WINDS...SPOTTY SHOWERS OR VIRGA
WILL BE POSSIBLE OVER THE HIGHER TERRAIN THIS EVENING. THIS WILL
CHANGE TOWARD MORNING AND ESPECIALLY TOMORROW AFTERNOON AS LIFT
AND INSTABILITY INCREASES. SHOWERS WILL BECOME WIDESPREAD OVER THE
MOUNTAINS ALONG WITH OCCASIONAL OBSCURATION OF THE TERRAIN.
VALLEYS A BIT MORE TRICKY AS FAR AS PRECIPITATION...BUT GUSTY
WINDS AND ISOLATED THUNDERSTORMS MAY IMPACT FORECAST TERMINAL
OPERATIONS THROUGH MUCH OF THE DAY.
&&
.FIRE WEATHER...
ISSUED AT 336 PM MDT FRI APR 18 2014
AS A LARGE LOW PRESSURE TROUGH MOVES ONSHORE OVER THE PACIFIC
NORTHWEST ON TUESDAY...STRONG SOUTHWEST FLOW WILL DEVELOP OVER
EASTERN UTAH AND WESTERN COLORADO. THIS FLOW WILL MIX INTO THE
VALLEYS BY THE AFTERNOON AND INCREASE OVER THE AREA AS A COLD FRONT
ASSOCIATED WITH THE TROUGH APPROACHES FROM THE NORTHWEST. AHEAD OF
THE FRONT CONDITIONS WILL REMAIN DRY...ESPECIALLY OVER SOUTHWEST
COLORADO AND SOUTHEAST UTAH WHERE MINIMUM RELATIVE HUMIDITY VALUES
WILL LIKELY DROP BELOW 15 PERCENT BELOW 8000 FEET. ALSO THE
STRONGEST WINDS ARE EXPECTED ACROSS EASTERN UTAH AND SOUTHWEST
COLORADO. THEREFORE CRITICAL WEATHER CONDITIONS WILL BE POSSIBLE
TUESDAY AFTERNOON IN AREAS WHERE FUELS ARE DRY. MODELS INDICATE THAT
THE BULK OF THE ENERGY AND MOISTURE ASSOCIATED WITH THE TROUGH WILL
REMAIN NORTH OF THE FORECAST AREA. LOW RELATIVE HUMIDITY AND GUSTY
WEST WINDS ARE EXPECTED OVER THE FAR SOUTHERN ZONES WEDNESDAY
AFTERNOON.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...NONE.
UT...NONE.
&&
$$
SHORT TERM...JAM
LONG TERM...EH
AVIATION...TGJT
FIRE WEATHER...EH
AREA FORECAST DISCUSSION
NWS MIAMI FL
557 PM EDT SAT APR 19 2014
.UPDATE...
UPDATED THE COASTAL WATERS FORECAST...MAINLY FOR THE WINDS ACROSS
THE REGION. REGIONAL OBSERVATIONS INDICATE THAT GENERALLY WEST TO
SOUTHWESTERLY WINDS IN THE 15 TO 20 KNOT RANGE CONTINUE ACROSS THE
REGIONAL WATERS...INCLUDING BISCAYNE BAY AND LAKE OKEECHOBEE.
EARLIER TODAY THERE WERE CONCERNS THAT SEAS COULD REACH 7 FEET IN
THE OFF SHORE GULF WATERS TONIGHT BUT RECENT MARINE GUIDANCE
INDICATES SEAS TO 6 FEET EXPECTED. A PRECAUTIONARY STATEMENT IS
IN EFFECT FOR ALL LOCAL WATERS...INCLUDING BISCAYNE BAY AND LAKE
OKEECHOBEE. THE LATEST GUIDANCE INDICATES WINDS ARE EXPECTED TO
SLOWLY SUBSIDE TONIGHT INTO SUNDAY WHILE REMAINING GENERALLY
WESTERLY TO NORTHWESTERLY.
60
&&
.PREV DISCUSSION... /ISSUED 211 PM EDT SAT APR 19 2014/
SHORT TERM...(TONIGHT-MONDAY NIGHT)...
THE AFTERNOON SURFACE ANALYSIS SHOWED THE COLD FRONT RESPONSIBLE FOR
THE ACTIVE START TODAY EXTENDING SSW FROM CAPE CANAVERAL TO KEY WEST
AND BREEZY WNW FLOW AND DRIER CONDITIONS FILLING IN BEHIND IT ALONG
THE GULF COAST. OBSERVATIONS REFLECT THIS BOUNDARY AND GENERALLY
SHOW A WEST TO EAST TEMP/DP GRADIENT ACROSS THE AREA TODAY FROM THE
GULF COAST TO THE ATLANTIC COAST. THE LATEST HRRR AND WRF
REFLECTIVITIES CONTINUE TO SHOW A FEW SHOWERS DEVELOPING ALONG THE
FRONT AS IT CONTINUES EAST THIS AFTERNOON TOWARD AND THROUGH THE
ATLANTIC COAST...MAINLY NORTH OF FORT LAUDERDALE TO THE PALM BEACH
COASTAL AREAS THROUGH THE LATE AFTERNOON HOURS. OTHERWISE...DRY
CONDITIONS ARE EXPECTED THROUGH THE REMAINDER OF THE WEEKEND AND
INTO THE UPCOMING WEEK WITH TEMPERATURES REMAINING AROUND NORMAL.
THE LATEST SHORT-RANGE MODEL GUIDANCE REFLECTS THIS DRY PATTERN AND
INDICATES THE UPPER LOW CENTERED NORTH OF THE AREA LIFTING NORTHEAST
THROUGH THIS TIME AS UPPER HEIGHTS RISE ACROSS THE REGION. ANOTHER
COLD FRONT...DRY...WILL MOVE SOUTH AND THROUGH THE STATE ON
MONDAY...WHICH WILL REINFORCE THE DRY AIR AND NORTHERLY FLOW OVER
THE STATE.
AG
LONG TERM...(TUESDAY-FRIDAY)
ANOTHER COLD FRONT WILL BE MOVING THROUGH SOUTH FLORIDA BY THE
MIDDLE OF NEXT WEEK FROM THE NORTH. HOWEVER...THE FRONT WILL BE A
DRY COLD FRONT WHICH WILL REINFORCE THE DRY AND PLEASANT WEATHER
OVER THE AREA THROUGH THE END OF THE PERIOD. TEMPERATURES ARE
FORECAST TO REMAIN AROUND NORMAL THROUGH THE WEEK AS THE LOW-LEVEL
FLOW SHIFTS TO THE SOUTHEAST AND UPPER HEIGHTS RISE.
BNB
AVIATION...
VFR CONDITIONS ARE EXPECTED TO CONTINUE THROUGH THE PERIOD. A FEW
SHOWERS...HOWEVER...CAN`T BE RULED OUT THROUGH THE LATE AFTERNOON
HOURS TODAY AS THE FRONT CONTINUES EAST ACROSS THE AREA. AT THIS
TIME...CONFIDENCE REMAINS TOO LOW TO INCLUDE IT IN THIS PACKAGE.
WINDS WILL START OUT FROM THE WEST...THEN GRADUALLY SHIFT TO THE NW
BY THE END OF THE PERIOD.
MARINE...
MUCH DRIER CONDITIONS WILL BE EXPECTED OVER THE REMAINDER OF THE
WEEKEND AS HIGH PRESSURE BUILDS EASTWARD OVER THE REGION IN THE WAKE
OF A COLD FRONT MOVING THROUGH THE AREA TODAY. A MODERATE NORTHERLY
SWELL WILL BE EXPECTED TO FILL IN ACROSS THE ATLANTIC WATERS MONDAY.
THIS SWELL COMBINED WITH MODERATE TO FRESH NORTHERLY WINDS WILL LEAD
TO ADVISORY LEVEL CONDITIONS FOR THE ATLANTIC WATERS THROUGH THIS
TIME EARLY NEXT WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 63 77 67 82 / 10 10 10 10
FORT LAUDERDALE 67 79 69 82 / 10 10 10 10
MIAMI 67 79 68 82 / 10 10 10 10
NAPLES 64 80 65 82 / 10 0 10 10
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
SHORT TERM...60/BD
LONG TERM....60/BD
AREA FORECAST DISCUSSION
NWS JACKSONVILLE FL
245 PM EDT SAT APR 19 2014
SHORT TERM /THROUGH MONDAY/...
SCATTERED SHOWERS AND AN ISOLATED TSTM OR TWO PREVAIL THIS AFTN AS
LOW PRESSURE PINWHEELS ACROSS THE INLAND FL/GA BORDER. THE LOW WILL
MOVE EAST INTO THE COASTAL WATERS THIS EVENING...EXITING TO THE NE
ACROSS THE WESTERN ATLANTIC SUNDAY. SCATTERED SHWRS WILL CONTINUE
ACROSS MOST AREAS THIS EVENING AS THE LOW MOVES ACROSS...GRADUALLY
DIMINISHING LATE THIS EVENING/OVERNIGHT AS THE LOW MOVES INTO THE
COASTAL WATERS. AS THE LOW EJECTS NE SUNDAY...EXPECT ONLY A FEW
SHOWERS OFFSHORE...WITH DRY CONDITIONS FOR ALL LAND AREAS.
HOWEVER...CLOUDY TO MOSTLY CLOUDY SKIES WILL PERSIST THROUGH SUNDAY
FOR ALL AREAS EXCEPT NORTH-CENTRAL FL WHERE SIGNIFICANT CLOUD BREAKS
WILL DEVELOP BY SUNDAY AFTN. BEHIND THE LOW...COOLER AIR WILL
FILTER IN...WITH LOWS TNGT IN THE LOWER/MID 50S INLAND AND 55 TO
60 COAST. HIGHS SUNDAY WILL RANGE FROM AROUND 70 ACROSS SE GA...WITH
MAINLY LOWER/MID 70S FOR NE FL.
SHORTWAVE RIDGE BUILDS OVER FORECAST AREA SUNDAY NIGHT AND MONDAY WITH
DRY CONDITIONS EXPECTED. HIGH TEMPS MONDAY WILL BE A BIT WARMER...AROUND
70 COAST TO NEAR 80 WESTERNMOST PART OF OUR FORECAST AREA.
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
POSITIVELY-TILTED SHORTWAVE TROUGH DIGS SE ACROSS AREA TUESDAY...MAY
SEE A FEW SHOWERS WITH FEATURE MAINLY OVER OUR GA COUNTIES...ACTIVITY
MAY DECREASE AS IT SPREADS OVER SE GA TUE NIGHT. KEPT POPS LOW AND
MAINLY ACROSS OUR GA COUNTIES FOR NOW.
NEXT RIDGE BUILDS OVER THE FORECAST AREA WED/THU...WITH DRY CONDITIONS
AND MILD TEMPS. NEXT STORM SYSTEM PASSES WELL NORTH OF FORECAST AREA
FRI/SAT...WITH WEAK COLD FRONT APPROACHING AREA FROM THE NW LATE SAT.
&&
.AVIATION...CHALLENGING CIG/VSBY FORECAST WITH LOW CIGS AND OCCASIONALLY
REDUCED VSBYS IN FOG/DZ/-RA AROUND UPPER LEVEL LOW PRESSURE OVER THE
AREA. MODEL GUIDANCE INCLUDING HRRR AND LAMP SUGGEST AFTER BRIEFING
HIGHER CONDITIONS IN NE FL CURRENTLY AHEAD OF SYSTEM...LOWER
CONDITIONS SPREAD IN FROM W TOWARD EVENING AND CONTINUE TONIGHT INTO
FIRST HALF OF SUN. FOLLOWED TREND OF KEEPING IFR CONDITIONS...THO
QUITE UNCERTAIN ON VSBYS TONIGHT WITH INCREASING NORTHERLY SURFACE
WINDS AROUND SURFACE LOW PRESSURE THAT WILL BE OFFSHORE.
NEVERTHELESS...FORECASTING IFR CONDITIONS AT TAFS SITES THRU SUN
MORNING.
&&
.MARINE...
A LULL IN WINDS/SEAS CONTINUES THIS AFTN JUST EAST OF LOW PRESSURE.
AS THE LOW MOVES INTO THE WATERS THIS EVENING AND EAST OF THE
WATERS BY SUNDAY...CONDITIONS WILL WORSEN RATHER QUICKLY...WITH
GALES LIKELY FOR MOST AREAS BY SUNDAY MORNING. THUS...WILL UPGRADE
THE GALE WATCH TO A WARNING FOR THE OUTER WATERS FOR OVERNIGHT TNGT
THROUGH SUNDAY EVENING. FOR THE NEARSHORE...WILL USE A SCA WITH
OCCASIONAL GUSTS TO GALE FORCE. SCA CONDITIONS WILL LINGER INTO
MONDAY FOR THE NEARSHORE WATERS...AND THROUGH MONDAY NIGHT FOR
THE OUTER WATERS. AFTER A BRIEF BREAK ON TUESDAY...ANOTHER ROUND
OF SCA WILL BE LIKELY TUESDAY NIGHT INTO WEDNESDAY. CONDITIONS
WILL IMPROVE FOR WEDNESDAY NIGHT/THURSDAY.
RIP CURRENTS: MODERATE RISK TODAY. MODERATE TO HIGH RISK SUNDAY
AND MONDAY WITH ELEVATED SURF.
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 52 70 51 78 / 30 10 10 10
SSI 57 67 54 68 / 50 20 10 10
JAX 55 72 54 76 / 50 10 0 10
SGJ 59 70 58 69 / 40 20 10 10
GNV 55 77 55 79 / 30 10 10 10
OCF 56 79 57 79 / 20 10 10 10
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GA...NONE.
AM...SMALL CRAFT ADVISORY FROM MIDNIGHT SUNDAY NIGHT TO 6 AM EDT
TUESDAY FOR ALTAMAHA SOUND GA TO FERNANDINA BEACH FL 20 NM
TO 60 NM OFFSHORE-FERNANDINA BEACH TO ST AUGUSTINE FL 20 NM
TO 60 NM OFFSHORE-ST AUGUSTINE TO FLAGLER BEACH FL 20 NM TO
60 NM OFFSHORE.
GALE WARNING FROM MIDNIGHT TONIGHT TO MIDNIGHT EDT SUNDAY NIGHT
FOR ALTAMAHA SOUND GA TO FERNANDINA BEACH FL 20 NM TO 60 NM
OFFSHORE-FERNANDINA BEACH TO ST AUGUSTINE FL 20 NM TO 60 NM
OFFSHORE-ST AUGUSTINE TO FLAGLER BEACH FL 20 NM TO 60 NM
OFFSHORE.
SMALL CRAFT ADVISORY FROM MIDNIGHT TONIGHT TO 7 AM EDT MONDAY
FOR ALTAMAHA SOUND GA TO FERNANDINA BEACH FL OUT 20 NM-
FERNANDINA BEACH TO ST AUGUSTINE FL OUT 20 NM-ST AUGUSTINE
TO FLAGLER BEACH FL OUT 20 NM.
&&
$$
WOLF/ALLEN/GUILLET
AREA FORECAST DISCUSSION
NWS MIAMI FL
211 PM EDT SAT APR 19 2014
.SHORT TERM...(TONIGHT-MONDAY NIGHT)...
THE AFTERNOON SURFACE ANALYSIS SHOWED THE COLD FRONT RESPONSIBLE FOR
THE ACTIVE START TODAY EXTENDING SSW FROM CAPE CANAVERAL TO KEY WEST
AND BREEZY WNW FLOW AND DRIER CONDITIONS FILLING IN BEHIND IT ALONG
THE GULF COAST. OBSERVATIONS REFLECT THIS BOUNDARY AND GENERALLY
SHOW A WEST TO EAST TEMP/DP GRADIENT ACROSS THE AREA TODAY FROM THE
GULF COAST TO THE ATLANTIC COAST. THE LATEST HRRR AND WRF
REFLECTIVITIES CONTINUE TO SHOW A FEW SHOWERS DEVELOPING ALONG THE
FRONT AS IT CONTINUES EAST THIS AFTERNOON TOWARD AND THROUGH THE
ATLANTIC COAST...MAINLY NORTH OF FORT LAUDERDALE TO THE PALM BEACH
COASTAL AREAS THROUGH THE LATE AFTERNOON HOURS. OTHERWISE...DRY
CONDITIONS ARE EXPECTED THROUGH THE REMAINDER OF THE WEEKEND AND
INTO THE UPCOMING WEEK WITH TEMPERATURES REMAINING AROUND NORMAL.
THE LATEST SHORT-RANGE MODEL GUIDANCE REFLECTS THIS DRY PATTERN AND
INDICATES THE UPPER LOW CENTERED NORTH OF THE AREA LIFTING NORTHEAST
THROUGH THIS TIME AS UPPER HEIGHTS RISE ACROSS THE REGION. ANOTHER
COLD FRONT...DRY...WILL MOVE SOUTH AND THROUGH THE STATE ON
MONDAY...WHICH WILL REINFORCE THE DRY AIR AND NORTHERLY FLOW OVER
THE STATE.
AG
.LONG TERM...(TUESDAY-FRIDAY)
ANOTHER COLD FRONT WILL BE MOVING THROUGH SOUTH FLORIDA BY THE
MIDDLE OF NEXT WEEK FROM THE NORTH. HOWEVER...THE FRONT WILL BE A
DRY COLD FRONT WHICH WILL REINFORCE THE DRY AND PLEASANT WEATHER
OVER THE AREA THROUGH THE END OF THE PERIOD. TEMPERATURES ARE
FORECAST TO REMAIN AROUND NORMAL THROUGH THE WEEK AS THE LOW-LEVEL
FLOW SHIFTS TO THE SOUTHEAST AND UPPER HEIGHTS RISE.
BNB
&&
.AVIATION...
VFR CONDITIONS ARE EXPECTED TO CONTINUE THROUGH THE PERIOD. A FEW
SHOWERS...HOWEVER...CAN`T BE RULED OUT THROUGH THE LATE AFTERNOON
HOURS TODAY AS THE FRONT CONTINUES EAST ACROSS THE AREA. AT THIS
TIME...CONFIDENCE REMAINS TOO LOW TO INCLUDE IT IN THIS PACKAGE.
WINDS WILL START OUT FROM THE WEST...THEN GRADUALLY SHIFT TO THE NW
BY THE END OF THE PERIOD.
&&
.MARINE...
MUCH DRIER CONDITIONS WILL BE EXPECTED OVER THE REMAINDER OF THE
WEEKEND AS HIGH PRESSURE BUILDS EASTWARD OVER THE REGION IN THE WAKE
OF A COLD FRONT MOVING THROUGH THE AREA TODAY. A MODERATE NORTHERLY
SWELL WILL BE EXPECTED TO FILL IN ACROSS THE ATLANTIC WATERS MONDAY.
THIS SWELL COMBINED WITH MODERATE TO FRESH NORTHERLY WINDS WILL LEAD
TO ADVISORY LEVEL CONDITIONS FOR THE ATLANTIC WATERS THROUGH THIS
TIME EARLY NEXT WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 63 77 67 82 / 10 10 10 10
FORT LAUDERDALE 67 79 69 82 / 10 10 10 10
MIAMI 67 79 68 82 / 10 10 10 10
NAPLES 64 80 65 82 / 10 0 10 10
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
SHORT TERM...84/AK
LONG TERM....85/AG
AREA FORECAST DISCUSSION
NWS MIAMI FL
145 AM EDT SAT APR 19 2014
.AVIATION...
CLUSTERS OF SHRAS AND TSRAS ARE BEGINNING TO DEVELOP ACROSS THE
GULF WATERS EARLY THIS MORNING AND SHOULD CONTINUE TO PUSH TO THE
NORTHEAST THROUGH THE MORNING. THIS ACTIVITY IS EXPECTED TO AFFECT
THE TAF SITES THROUGH THE MORNING BUT INTENSITY AND COVERAGE IS
STILL IN QUESTION...SO COVERED WITH VCSH AT ALL SITES FOR NOW.
WILL AMEND AS NECESSARY. OTHERWISE...GENERALLY SOUTHERLY FLOW WILL
TURN MORE SOUTHWESTERLY THEN WESTERLY THROUGH THE DAY AS THE COLD
FRONT APPROACHES.
&&
.PREV DISCUSSION... /ISSUED 850 PM EDT FRI APR 18 2014/
UPDATE...
SCATTERED SHOWERS WILL CONTINUE ACROSS THE LAKE REGION THROUGH THE EVENING.
ALTHOUGH LIMITED CONVECTION HAS HAPPENED... SATELLITE IMAGERY
CONTINUES TO SHOW THE UPPER LEVEL LOW DIGGING INTO THE GULF WATERS
TONIGHT. CURRENT GUIDANCE KEEPS THIS LOW APPROACHING THE PENINSULA
OVERNIGHT AND MOVING IT ACROSS THE AREA TOMORROW...WITH A
MOISTURE CONVERGENCE ZONE ACROSS SOUTH FLORIDA BY 06Z AND ENOUGH
VERTICAL MOTION AS OUR AREA REMAINS EAST OF THE TROUGH AXIS. IF
THESE CONDITIONS MATERIALIZE...SHOWERS AND A FEW THUNDERSTORMS
COULD BE EXPECTED. ON THE OTHER HAND...THE LATEST HRRR RUN SHOWS
MOSTLY SHOWERS DEVELOPING ACROSS THE WEST COAST BY 04Z AND MOVING
EAST REACHING THE EAST COAST BY 08Z.
SO WHATS THE FORECAST? SHOWERS AND THUNDERSTORMS ARE STILL
EXPECTED TONIGHT ALTHOUGH THE THUNDERSTORM POTENTIAL IS
LOW. THEREFORE...NO CHANGES TO THE FORECAST PACKAGE WAS NEEDED.
THE POTENTIAL FOR STRONG ACTIVITY IS STILL PRESENT...THEREFORE
CANNOT RULE OUT THAT POSSIBILITY.
PREV DISCUSSION... /ISSUED 218 PM EDT FRI APR 18 2014/
NEAR TERM...(TONIGHT THROUGH SATURDAY MORNING)
THE INITIAL CONCERN WILL BE THROUGH THE EVENING AND OVERNIGHT PERIOD
TONIGHT DUE TO THE POTENTIAL FOR STRONG TO SEVERE THUNDERSTORMS
AND HEAVY RAINFALL ASSOCIATED WITH A FRONTAL BOUNDARY APPROACHING
THE AREA FROM THE GULF. THE LATEST RADAR LOOP SHOWED A FAIRLY
PRONOUNCED SQUALL LINE WITHIN 60-100 NM WEST OF NAPLES. THE LATEST
HRRR AND WRF MODELS HAVE INITIALIZED FAIRLY WELL WITH THE CURRENT
TRENDS AND GENERALLY INDICATE A NARROW SQUALL LINE CONTINUING
EASTWARD AND HOLDING TOGETHER AS IT MOVES ASHORE FROM NAPLES TO
THE LAKE REGION BETWEEN 3Z AND 6Z. THE STORM PREDICTION CENTER
(SPC) HAS INCLUDED THIS AREA IN A SLIGHT RISK OF SEVERE
THUNDERSTORMS WITH THE MAIN THREAT BEING STRAIGHT-LINE WINDS.
THIS LINE IS THEN PROJECTED TO CONTINUE EASTWARD TOWARD THE EAST
COAST FROM 6Z TO 10Z, THEN BEGINNING TO PUSH OFF THE EAST COAST BY
OR AROUND DAYBREAK SATURDAY MORNING. ALTHOUGH SPC HAS INCLUDED
NAPLES TO THE LAKE IN THE SLIGHT RISK OF SEVERE THUNDERSTORMS
THROUGH THIS TIME...THE BEST CHANCE FOR A SEVERE THUNDERSTORM OR
TORNADO WATCH WILL REMAIN NORTH OF OUR LOCAL AREA ACROSS
CENTRAL/NCNTRAL FLORIDA. FLOODING SHOULDN`T BE AN ISSUE DUE TO THE
PROGRESSIVE NATURE EXPECTED WITH THIS NARROW LINE AS IT QUICKLY
TRAVERSES THE AREA FROM WEST TO EAST.
85/AG
SHORT TERM...(SATURDAY-SUNDAY NIGHT)...
THE FRONTAL BOUNDARY IS PROGGED TO MOVE EAST OF THE LOCAL AREA WITH
DRIER AIR AND NW FLOW FILLING IN SATURDAY THROUGH SATURDAY NIGHT AS
THE UPPER LOW BEGINS TO LIFT OUT TO THE NORTHEAST. THE LATEST
TEMPERATURE GUIDANCE INDICATES CONDITIONS TRENDING BACK TO AROUND
NORMAL TO SLIGHTLY BELOW NORMAL INLAND LATE SATURDAY NIGHT THROUGH
DAYBREAK SUNDAY MORNING IN THE WAKE OF THE FRONT. DEEP LAYER RIDGE
WILL BEGIN TO BUILD EASTWARD ACROSS THE REGION WITH DRY CONDITIONS
CONTINUING THROUGH THE END OF THE PERIOD.
85/AG
LONG TERM...(SUNDAY-EARLY NEXT WEEK)
THE DRY WEATHER WILL CONTINUE OVER SOUTH FLORIDA FOR MOST OF NEXT
WEEK DUE TO THE HIGH OVER THE AREA EARLY NEXT WEEK FOLLOWED BY A DRY
COLD FRONT PUSHING THROUGH THE AREA DURING THE MIDDLE PART OF NEXT
WEEK.
BNB
MARINE...
A COLD FRONT WILL MOVE THROUGH THE MARINE AREA TONIGHT INTO SATURDAY
MORNING WITH NEAR ADVISORY LEVEL NORTHWEST WINDS EXPECTED TO FILL IN
BEHIND IT SATURDAY. HEAVY SHOWERS AND THUNDERSTORMS WILL REMAIN
POSSIBLE THIS EVENING INTO TONIGHT ACROSS THE GULF WATERS...THEN
ACROSS THE ATLANTIC WATERS LATE TONIGHT THROUGH THE MORNING HOURS
SATURDAY. MUCH DRIER CONDITIONS WILL BE EXPECTED OVER THE WEEKEND AS
HIGH PRESSURE BUILDS EASTWARD OVER THE REGION. A MODERATE NORTHERLY
SWELL WILL BE EXPECTED TO FILL IN ACROSS THE ATLANTIC WATERS MONDAY.
THIS SWELL COMBINED WITH MODERATE TO FRESH NORTHERLY WINDS WILL LEAD
TO ADVISORY LEVEL CONDITIONS FOR THE ATLANTIC WATERS THROUGH THIS
TIME EARLY NEXT WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 84 63 81 68 / 30 10 0 0
FORT LAUDERDALE 87 67 82 70 / 40 0 0 0
MIAMI 86 68 83 69 / 40 0 0 0
NAPLES 84 61 82 66 / 20 10 10 0
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
635 PM CDT Sun Apr 20 2014
...Updated for the aviation discussion...
.SHORT TERM...(This evening through Monday)
ISSUED AT 116 PM CDT SUN APR 20 2014
Ample insolation early this afternoon resulted in surface-based CAPE
in the 700-1100 J/kg west of Highway 283 to the Colorado border.
Lack of a capping inversion beneath cool temperatures in the
700-500mb layer (+2C at 700mb). There were two areas of surface
convergence that will support development of thunderstorms by
mid-afternoon. The first area is near the Colorado border along the
stationary trough axis, which is also near where the mid level
vorticity center is. We are also watching a secondary area of
interest from Dodge City south to the Oklahoma border where surface
wind convergence was slightly enhanced. 1km visible satellite
confirmed development of cumulus in both of these areas. Given the
higher degree of instability than earlier anticipated, a few hail
storms may occur with the largest hail most likely being around
1-inch in diameter (Quarter size). Severe weather threat will likely
wane after 00Z or so as showers and thunderstorms grow upscale. This
is what the HRRR would seem to suggest in its latest runs, which
makes sense given the marginal instability. Much of the
precipitation should be coming to an end/or exiting the southwest
Kansas region in the 04-07Z time frame so POPs will be lowered
during this time frame and shortly thereafter.
A northern stream shortwave trough will aid in bringing a cold front
south through western Nebraska late tonight, reaching southwestern
Kansas by mid to late morning Monday. The front is not expected to
have any impact on temperatures, though, so the going forecast of
upper 70s to near 80 still looks pretty good (especially along/south
of the Arkansas River).
.LONG TERM...(Monday night through Sunday)
ISSUED AT 149 PM CDT SUN APR 20 2014
Upper level ridging builds over the Plains Monday night through
Tuesday with dry conditions in the mid levels. This will allow
mostly clear skies to be observed across western Kansas. This will
be short lived as the next storm system moves into the Northern
Rockies Tuesday night into Wednesday. Southerly winds will be felt
across western Kansas as this system approaches with increasing mid
level moisture Tuesday night. A moderate upper level jet will be
found above western Kansas on Wednesday enhancing lift across the
area. Southerly winds will continue at the surface becoming windy in
the afternoon. In addition, a dryline is suggested to develop in the
afternoon with CAPE and shear increasing as the day progresses.
These conditions will bring a chance of thunderstorms ahead of the
dryline from late afternoon into Wednesday night. A few of these
storms could become strong to severe with large hail and damaging
winds being the main concern. A cold front then moves through
western Kansas Thursday morning shifting winds to the north. Lows
Tuesday morning will be in the low to mid 40s with highs Tuesday
reaching into the upper 70s and lower 80s. The warmest day of the
week looks to be on Wednesday with lows in the mid 50s and highs in
the lower 80s. Lows Thursday morning look to range from the mid 40s
across west central Kansas where the aforementioned cold front is
expected to move through early to upper 50s across south central
Kansas where the front is not expected to move through by sunrise.
Dry conditions are then expected during the remainder of the week as
an upper level ridge builds above the Plains with dry conditions in
the mid levels. Winds shift back to the south by Saturday as the
next storm system entered the western United States. This system is
expected to affect western Kansas this weekend bringing an increase
in clouds and a chance of thunderstorms. Highs Thursday through this
weekend will generally be in the 70s with lower 80s possible across
far southwestern Kansas on Saturday. Lows will generally be in the
mid to upper 40s Friday and Saturday morning.
&&
.AVIATION...(For the 00Z TAFS through 00Z Monday evening)
ISSUED AT 628 PM CDT SUN APR 20 2014
An upper level low pressure area slowly moving east across western
Kansas will keep the area unstable through at least 03z tonight.
The area of instability will shift to the east after that, and mid
level clouds will be left behind. Winds in and near the upper low
pressure will be south to southeast at 15g25kt this evening, then
become southeast at 10 knots or less after 04z. After 15z on
Monday, expect sct cirrus clouds and north winds of 15g22kt.
Overall, flight conditions will be VFR, except with a few MVFR
cigs in widely scattered showers and thunderstorms early tonight.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 53 77 45 79 / 50 10 0 10
GCK 51 76 43 82 / 50 0 0 10
EHA 49 76 46 83 / 20 10 0 10
LBL 51 78 46 83 / 50 0 0 10
HYS 56 77 43 79 / 60 10 0 10
P28 56 77 47 79 / 50 10 0 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Umscheid
LONG TERM...Hovorka_42
AVIATION...Burke
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1127 AM MDT SAT APR 19 2014
.UPDATE...
ISSUED AT 1019 AM MDT SAT APR 19 2014
AT 16Z...COLD FRONT LIES NEAR A MCCOOK TO GOODLAND LINE WITH WINDS
SHIFTING TO NORTHEAST WITH FRONTAL PASSAGE. AS THE FRONT CONTINUES
TO MOVE SOUTH THIS AFTERNOON...IT WILL BE THE FOCUS FOR ISOLATED
TO WIDELY SCATTERED CONVECTION. LATEST HIGH RESOLUTION MODELS RUNS
PLACE THE FRONT NEAR A NORTON TO CHEYENNE WELLS LINE AT PEAK
HEATING. INSTABILITY AXIS JUST AHEAD OF THE FRONT WILL BE 800-1200
J/KG WITH LITTLE IF ANY SURFACE BASED INSTABILITY NORTH OF THE
FRONT. DEEP LAYER SHEAR IS FORECAST TO BE 15-25KTS IN THE
INSTABILITY AXIS. GIVEN THOSE PARAMETERS...THE SEVERE THREAT
APPEARS RATHER LOW. WHILE AN ISOLATED STRONGER STORM CAPABLE OF
PRODUCING QUARTER SIZED HAIL CANNOT BE COMPLETELY RULED OUT...MOST
IF NOT ALL STORMS WILL LIKELY STAY BELOW SEVERE LIMITS.
PRECIPITATION WILL EXPAND IN AREAL COVERAGE THROUGH THE EVENING
HOURS AS THE MAIN SYNOPTIC SCALE FORCING ARRIVES WITH THE UPPER
SHORTWAVE TROUGH. EASTERN PORTIONS OF THE AREA LOOK TO RECEIVE THE
MOST QPF...GENERALLY AROUND A QUARTER OF AN INCH WITH UP TO A HALF
AN INCH POSSIBLE NEAR STRONGER STORMS...WITH LESSER AMOUNTS ELSEWHERE.
&&
.SHORT TERM...(TODAY THROUGH MONDAY NIGHT)
ISSUED AT 341 AM MDT SAT APR 19 2014
FORECAST PROBLEM WILL BE CHANCE OF PRECIPITATION THROUGH THE WEEKEND.
SATELLITE SHOWING AN ACTIVE AND PROGRESSIVE FLOW OVER THE PACIFIC.
THIS TRANSLATES TO A SPLIT FLOW OVER THE COUNTRY WITH A FASTER
NORTHERN STREAM AND A SLOWER/MORE CUTOFF SOUTHERN STREAM. STRONGER
NORTHERN STREAM SYSTEM NOW ALONG THE UNITED STATES/CANADIAN BORDER
IS PUSHING A FRONT TOWARD THE AREA. CLOSED OFF LOW IS OVER SOUTHERN
CALIFORNIA/NORTHERN BAJA. ABOVE MENTIONED COLD FRONT LOOKS TO BE
RAPIDLY APPROACHING THE AREA.
AT JET LEVEL...MODELS NOT DOING THE GREATEST. THE GFS AND CANADIAN
APPEAR TO BE DOING THE BEST WITH THE ECMWF JUST BEHIND THEM. AT MID
LEVELS...ANALYSIS AND SATELLITE SHOW THAT THE CANADIAN IS DOING THE
BEST WITH THE DESERT SOUTHWEST LOW. FOR THE NORTHERN STREAM SYSTEM
THE MODELS TENDED TO NOT HAVE IT FAR ENOUGH SOUTH . HERE THE CANADIAN
WAS DOING A LITTLE BETTER THAN THE GFS. THE MODELS ARE HAVING A VERY
HARD TIME WITH THE SURFACE WIND AND PRESSURE FIELD. THE RUC AND NAM
TENDED TO BE TOO FAR FAST WITH LEE SIDE TROUGH AND ESPECIALLY THE
FRONT. HOWEVER THE OTHER OUTPUT TENDED TO BE TOO SLOW.
VERY COMPLICATED SITUATION AS EVIDENCED BY THE MODEL DIFFERENCES AND
CHANGES IN THE MODEL OUTPUT OVER THE LAST 24 HOURS. CONFIDENCE IS
BELOW AVERAGE IN THE PRECIPITATION FORECAST AND TO SOME DEGREE HOW
THE HIGH TEMPERATURE FORECAST WORK OUT.
TODAY/TONIGHT...MODELS ARE ALL OVER THE PLACE WITH THE SPEED AND
POSITION OF THE FRONT WHICH AFFECTS EVERYTHING ABOUT THE FORECAST.
FASTER MODELS HAVE THE FRONT THROUGH OF THE AREA BY LATE IN THE
AFTERNOON. SOME BRING IT IN FASTER AND THEN SLOW IT/HANG IT UP.
OTHERS STILL ONLY BRING THE FRONT INTO THE NORTHWEST HALF BY LATE
IN THE DAY. TENDED TO GO INTO THE MIDDLE OF THE ROAD.
BLENDING ALL MODEL SOLUTIONS TOGETHER TODAY WOULD SAY THAT
THUNDERSTORMS COULD HAPPEN ABOUT ANYWHERE THIS AFTERNOON. A COUPLE
OF THINGS CONSISTENT FROM YESTERDAY ARE THE MODEL TENDENCIES OF
SLOWING THE SYSTEM DOWN AND HAVING IT MORE CLOSED BY THE TIME IT
MOVES INTO THE AREA TONIGHT. MODELS HAVE BACKED OFF ON THE CHANCE
OF PRECIPITATION FOR TODAY AND THAT SEEMS REASONABLE. CONSIDERING THE
LACK OF SIGNIFICANT LIFT ALOFT AND THE POSSIBILITY OF BEING CAPPED
SUPPORTS THAT. SO REDUCED THE CHANCES FOR THE DAY. DESPITE
DIFFERENCES IN THE FRONTAL POSITION...MODELS DO SHOW IT COMING A
LITTLE FURTHER SOUTH PLUS LOOK TO HAVE A DECENT AMOUNT OF HIGHER
LEVEL CLOUD COVER. SO DID REDUCE MAXES A LITTLE.
MODEL DIFFERENCES CONTINUE TONIGHT. HOWEVER...MODELS DO BRING IN
MUCH BETTER LIFT BUT THEY DIFFER ON WHERE THEY WANT TO PUT IT. TO
COMPLICATE MATTERS IT LOOKS LIKE A FEW OF THE MODELS MAY BE
SUFFERING FROM CONVECTIVE FEEDBACK. DUE TO THE SLOWER TRENDS MODELS
LOOK TO HOLD BACK THE MAIN LIFT UNTIL LATER TONIGHT. ALL THINGS
CONSIDERED KEPT THE POPS IN THE HIGH CHANCE CATEGORY. YESTERDAY
CONCERN WAS THAT LOCALLY HEAVY RAINFALL WOULD BE A PROBLEM. THE
POTENTIAL IS DEFINITELY THERE DUE TO THE HIGH PWATS THAT ARE WAY
ABOVE NORMAL. HOWEVER...DUE TO MODEL DIFFICULTIES HAVING A HARD
SPECIFYING ANY SPECIFIC AREA OR EVEN MENTION IT AT ALL.
SUNDAY/SUNDAY NIGHT...MODELS ARE A LITTLE CLOSER FOR THIS PERIOD
THAN FOR SATURDAY AND SATURDAY NIGHT. SYSTEM IS CLOSED OFF AND NEAR
OR OVER THE WESTERN HALF OF THE AREA AT THE BEGINNING. FRONT HAS
PULLED BACK FURTHER WEST TO NEAR THE COLORADO AND KANSAS BORDER...IF
YOU BELIEVE THE FURTHEST WEST SOLUTION. AS YESTERDAY THE GREATEST
THREAT OF PRECIPITATION IS IN THE EASTERN HALF TO TWO THIRDS WHERE
LOCALLY HEAVY RAINFALL COULD STILL BE A THREAT. PRECIPITATION SHOULD
END DURING THE EVENING. HIGH TEMPERATURES WILL DEPEND ON HOW
EXTENSIVE PRECIPITATION WILL BE. TENDED TO KEEP TEMPERATURES ABOUT
THE SAME IF NOT SLIGHTLY COOLER.
MONDAY/MONDAY NIGHT...SHORTWAVE RIDGING ALOFT MOVES INTO THE AREA AS
NORTHERLY WINDS AT THE SURFACE PUSH IN BEHIND THE EXITING SYSTEM.
ONLY MADE A SLIGHT ADJUSTMENT TO THE MAXES BUT FEEL THAT THE MODELS
MAY BE HAVING THE TEMPERATURES TOO COOL.
.LONG TERM...(TUESDAY THROUGH FRIDAY)
ISSUED AT 220 AM MDT SAT APR 19 2014
TUESDAY...UPPER RIDGE MOVES OVER THE AREA AHEAD OF A LARGE UPPER
TROUGH WHICH BY 12Z WEDNESDAY SHIFTS TOWARD THE NORTHERN
ROCKIES...SHIFTING THE UPPER FLOW TO THE SOUTHWEST. AT THE SFC
INCREASING PRESSURE GRADIENT BETWEEN SFC HIGH TO OUR EAST AND LOW
PRESSURE TO OUR WEST. THIS WILL PRODUCE BREEZY TO WINDY SOUTHERLY
WINDS. TOWARD THE END OF THE DAY DRYLINE EDGES EAST INTO FAR EASTERN
COLORADO. LOW LEVEL CONVERGENCE ALONG THE DRYLINE COUPLED WITH SOME
WEAK INSTABILITY MAY BE ENOUGH TO PRODUCE SOME ISOLATED
THUNDERSTORMS. FOR NOW HAVE KEPT THEM OUT DURING THE DAY BUT KEPT
THEM IN EARLY TUESDAY NIGHT ACROSS THE FAR EAST. HIGH TEMPERATURES
IN THE MID 70S EAST TO NEAR 80 WEST. LOWS TUESDAY NIGHT GENERALLY IN
THE 50S.
WEDNESDAY...CENTER OF UPPER TROUGH EXPECTED TO MOVE EAST INTO THE
NORTHERN PLAINS WHILE AT THE SFC WINDY/VERY WINDY CONDITIONS
EXPECTED DURING PART/MOST OF THE DAY BEFORE A COLD FRONT MOVES
THROUGH...MOST LIKELY LATE IN THE DAY AND CERTAINLY (AT THIS POINT)
WEDNESDAY NIGHT. A WIND ADVISORY MAY BE NEEDED FOR PARTS OF THE AREA
WHERE GUSTS TO 50 MPH POSSIBLE. INSTABILITY AXIS SETS UP ACROSS THE
FAR EASTERN 1/4 OF THE AREA WHERE CURRENT FORECAST HAS SLIGHT CHANCE
POPS FOR THUNDERSTORMS. SEE NO REASON TO MAKE ADJUSTMENTS TO THIS
THINKING. INSTABILITY AXIS MOVES EAST OF THE AREA WEDNESDAY EVENING
AS COLD FRONT AND WIND SHIFT MOVES IN AND ANY PRECIPITATION CHANCES
LOOK TO BE CONFINED TO THE BEFORE MIDNIGHT PERIOD...CURRENTLY
HANDLED WELL IN CURRENT FORECAST. HIGH TEMPERATURES MID 70S TO
AROUND 80 IN EASTERN COLORADO WITH LOW 80S EAST OF THE CO/KS BORDER.
LOWS WEDNESDAY NIGHT UPPER 30S TO LOW 40S WEST...LOW 40S TO AROUND
50 EAST OF THE CO/KS BORDER.
THURSDAY...UPPER LOW AND ASSOCIATED TROUGH CONTINUE SLOWLY EAST
WHILE SFC FEATURES SHOW NORTHWEST WINDS OVER THE AREA ALONG WITH
COOLER TEMPERATURES. NO PRECIPITATION EXPECTED. HIGH TEMPERATURES
GENERALLY IN THE 60S EXCEPT NEAR 70 BY HILL CITY. LOWS MID TO UPPER
30S WEST...LOW 40S EAST.
FRIDAY...AS UPPER LOW MOVES INTO THE GREAT LAKES WE AWAIT SOME UPPER
RIDGING THAT MOVES IN FRIDAY NIGHT AS ANOTHER STORM SYSTEM MAKES ITS
WAY TOWARD THE PACIFIC NORTHWEST COAST. LOOKS LIKE ANOTHER DRY
PERIOD WITH TEMPERATURES NEAR TO SLIGHTLY ABOVE NORMAL. HIGH
TEMPERATURES GENERALLY IN THE 60S EXCEPT AROUND 70 ACROSS THE FAR
SOUTH. LOWS UPPER 30S WEST TO LOW 40S EAST OF THE CO/KS BORDER.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1123 AM MDT SAT APR 19 2014
VFR EXPECTED AT BOTH KGLD AND KMCK THROUGH THE PERIOD. FRONTAL
PASSAGE HAS OCCURRED AT BOTH TERMINALS AND NORTHERLY SURFACE WINDS
WILL GRADUALLY DECREASE THROUGH THE REST OF THE DAY. THUNDERSTORMS
WILL INITIATE NEAR THE FRONT LATER THIS AFTERNOON...WELL SOUTH OF
BOTH TERMINALS...BUT WILL MOVE NORTH TONIGHT. INSTABILITY WILL BE
VERY LIMITED NORTH OF THE FRONT...BUT CANNOT COMPLETELY RULE OUT
AN ISOLATED THUNDERSTORM BRIEFLY IMPACTING A TERMINAL MAINLY THIS
EVENING. RAIN CHANCES WILL CONTINUE OVERNIGHT AND INTO SUNDAY
MORNING BUT AGAIN BEST CHANCES WILL BE TO THE SOUTH SO WILL NOT
MENTION IN EITHER TAF AT THIS POINT.
&&
.FIRE WEATHER...
ISSUED AT 220 AM MDT SAT APR 19 2014
CRITICAL FIRE WEATHER CONDITIONS ARE POSSIBLE FROM AROUND NOON
MDT (1 PM CDT) WEDNESDAY AFTERNOON THROUGH 7 PM MDT (8 PM CDT)
WEDNESDAY EVENING FOR LOCATIONS GENERALLY ALONG AND WEST OF THE
CO/KS BORDER. IN THIS AREA RELATIVE HUMIDITY IS FORECAST TO DROP
TOWARD 15 PERCENT WITH SOUTHWEST WINDS GUSTING 40 TO 45 MPH.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...024
SHORT TERM...BULLER
LONG TERM...99
AVIATION...024
FIRE WEATHER...99
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1032 AM MDT SAT APR 19 2014
.UPDATE...
ISSUED AT 1019 AM MDT SAT APR 19 2014
AT 16Z...COLD FRONT LIES NEAR A MCCOOK TO GOODLAND LINE WITH WINDS
SHIFTING TO NORTHEAST WITH FRONTAL PASSAGE. AS THE FRONT CONTINUES
TO MOVE SOUTH THIS AFTERNOON...IT WILL BE THE FOCUS FOR ISOLATED
TO WIDELY SCATTERED CONVECTION. LATEST HIGH RESOLUTION MODELS RUNS
PLACE THE FRONT NEAR A NORTON TO CHEYENNE WELLS LINE AT PEAK
HEATING. INSTABILITY AXIS JUST AHEAD OF THE FRONT WILL BE 800-1200
J/KG WITH LITTLE IF ANY SURFACE BASED INSTABILITY NORTH OF THE
FRONT. DEEP LAYER SHEAR IS FORECAST TO BE 15-25KTS IN THE
INSTABILITY AXIS. GIVEN THOSE PARAMETERS...THE SEVERE THREAT
APPEARS RATHER LOW. WHILE AN ISOLATED STRONGER STORM CAPABLE OF
PRODUCING QUARTER SIZED HAIL CANNOT BE COMPLETELY RULED OUT...MOST
IF NOT ALL STORMS WILL LIKELY STAY BELOW SEVERE LIMITS.
PRECIPITATION WILL EXPAND IN AREAL COVERAGE THROUGH THE EVENING
HOURS AS THE MAIN SYNOPTIC SCALE FORCING ARRIVES WITH THE UPPER
SHORTWAVE TROUGH. EASTERN PORTIONS OF THE AREA LOOK TO RECEIVE THE
MOST QPF...GENERALLY AROUND A QUARTER OF AN INCH WITH UP TO A HALF
AN INCH POSSIBLE NEAR STRONGER STORMS...WITH LESSER AMOUNTS ELSEWHERE.
&&
.SHORT TERM...(TODAY THROUGH MONDAY NIGHT)
ISSUED AT 341 AM MDT SAT APR 19 2014
FORECAST PROBLEM WILL BE CHANCE OF PRECIPITATION THROUGH THE WEEKEND.
SATELLITE SHOWING AN ACTIVE AND PROGRESSIVE FLOW OVER THE PACIFIC.
THIS TRANSLATES TO A SPLIT FLOW OVER THE COUNTRY WITH A FASTER
NORTHERN STREAM AND A SLOWER/MORE CUTOFF SOUTHERN STREAM. STRONGER
NORTHERN STREAM SYSTEM NOW ALONG THE UNITED STATES/CANADIAN BORDER
IS PUSHING A FRONT TOWARD THE AREA. CLOSED OFF LOW IS OVER SOUTHERN
CALIFORNIA/NORTHERN BAJA. ABOVE MENTIONED COLD FRONT LOOKS TO BE
RAPIDLY APPROACHING THE AREA.
AT JET LEVEL...MODELS NOT DOING THE GREATEST. THE GFS AND CANADIAN
APPEAR TO BE DOING THE BEST WITH THE ECMWF JUST BEHIND THEM. AT MID
LEVELS...ANALYSIS AND SATELLITE SHOW THAT THE CANADIAN IS DOING THE
BEST WITH THE DESERT SOUTHWEST LOW. FOR THE NORTHERN STREAM SYSTEM
THE MODELS TENDED TO NOT HAVE IT FAR ENOUGH SOUTH . HERE THE CANADIAN
WAS DOING A LITTLE BETTER THAN THE GFS. THE MODELS ARE HAVING A VERY
HARD TIME WITH THE SURFACE WIND AND PRESSURE FIELD. THE RUC AND NAM
TENDED TO BE TOO FAR FAST WITH LEE SIDE TROUGH AND ESPECIALLY THE
FRONT. HOWEVER THE OTHER OUTPUT TENDED TO BE TOO SLOW.
VERY COMPLICATED SITUATION AS EVIDENCED BY THE MODEL DIFFERENCES AND
CHANGES IN THE MODEL OUTPUT OVER THE LAST 24 HOURS. CONFIDENCE IS
BELOW AVERAGE IN THE PRECIPITATION FORECAST AND TO SOME DEGREE HOW
THE HIGH TEMPERATURE FORECAST WORK OUT.
TODAY/TONIGHT...MODELS ARE ALL OVER THE PLACE WITH THE SPEED AND
POSITION OF THE FRONT WHICH AFFECTS EVERYTHING ABOUT THE FORECAST.
FASTER MODELS HAVE THE FRONT THROUGH OF THE AREA BY LATE IN THE
AFTERNOON. SOME BRING IT IN FASTER AND THEN SLOW IT/HANG IT UP.
OTHERS STILL ONLY BRING THE FRONT INTO THE NORTHWEST HALF BY LATE
IN THE DAY. TENDED TO GO INTO THE MIDDLE OF THE ROAD.
BLENDING ALL MODEL SOLUTIONS TOGETHER TODAY WOULD SAY THAT
THUNDERSTORMS COULD HAPPEN ABOUT ANYWHERE THIS AFTERNOON. A COUPLE
OF THINGS CONSISTENT FROM YESTERDAY ARE THE MODEL TENDENCIES OF
SLOWING THE SYSTEM DOWN AND HAVING IT MORE CLOSED BY THE TIME IT
MOVES INTO THE AREA TONIGHT. MODELS HAVE BACKED OFF ON THE CHANCE
OF PRECIPITATION FOR TODAY AND THAT SEEMS REASONABLE. CONSIDERING THE
LACK OF SIGNIFICANT LIFT ALOFT AND THE POSSIBILITY OF BEING CAPPED
SUPPORTS THAT. SO REDUCED THE CHANCES FOR THE DAY. DESPITE
DIFFERENCES IN THE FRONTAL POSITION...MODELS DO SHOW IT COMING A
LITTLE FURTHER SOUTH PLUS LOOK TO HAVE A DECENT AMOUNT OF HIGHER
LEVEL CLOUD COVER. SO DID REDUCE MAXES A LITTLE.
MODEL DIFFERENCES CONTINUE TONIGHT. HOWEVER...MODELS DO BRING IN
MUCH BETTER LIFT BUT THEY DIFFER ON WHERE THEY WANT TO PUT IT. TO
COMPLICATE MATTERS IT LOOKS LIKE A FEW OF THE MODELS MAY BE
SUFFERING FROM CONVECTIVE FEEDBACK. DUE TO THE SLOWER TRENDS MODELS
LOOK TO HOLD BACK THE MAIN LIFT UNTIL LATER TONIGHT. ALL THINGS
CONSIDERED KEPT THE POPS IN THE HIGH CHANCE CATEGORY. YESTERDAY
CONCERN WAS THAT LOCALLY HEAVY RAINFALL WOULD BE A PROBLEM. THE
POTENTIAL IS DEFINITELY THERE DUE TO THE HIGH PWATS THAT ARE WAY
ABOVE NORMAL. HOWEVER...DUE TO MODEL DIFFICULTIES HAVING A HARD
SPECIFYING ANY SPECIFIC AREA OR EVEN MENTION IT AT ALL.
SUNDAY/SUNDAY NIGHT...MODELS ARE A LITTLE CLOSER FOR THIS PERIOD
THAN FOR SATURDAY AND SATURDAY NIGHT. SYSTEM IS CLOSED OFF AND NEAR
OR OVER THE WESTERN HALF OF THE AREA AT THE BEGINNING. FRONT HAS
PULLED BACK FURTHER WEST TO NEAR THE COLORADO AND KANSAS BORDER...IF
YOU BELIEVE THE FURTHEST WEST SOLUTION. AS YESTERDAY THE GREATEST
THREAT OF PRECIPITATION IS IN THE EASTERN HALF TO TWO THIRDS WHERE
LOCALLY HEAVY RAINFALL COULD STILL BE A THREAT. PRECIPITATION SHOULD
END DURING THE EVENING. HIGH TEMPERATURES WILL DEPEND ON HOW
EXTENSIVE PRECIPITATION WILL BE. TENDED TO KEEP TEMPERATURES ABOUT
THE SAME IF NOT SLIGHTLY COOLER.
MONDAY/MONDAY NIGHT...SHORTWAVE RIDGING ALOFT MOVES INTO THE AREA AS
NORTHERLY WINDS AT THE SURFACE PUSH IN BEHIND THE EXITING SYSTEM.
ONLY MADE A SLIGHT ADJUSTMENT TO THE MAXES BUT FEEL THAT THE MODELS
MAY BE HAVING THE TEMPERATURES TOO COOL.
.LONG TERM...(TUESDAY THROUGH FRIDAY)
ISSUED AT 220 AM MDT SAT APR 19 2014
TUESDAY...UPPER RIDGE MOVES OVER THE AREA AHEAD OF A LARGE UPPER
TROUGH WHICH BY 12Z WEDNESDAY SHIFTS TOWARD THE NORTHERN
ROCKIES...SHIFTING THE UPPER FLOW TO THE SOUTHWEST. AT THE SFC
INCREASING PRESSURE GRADIENT BETWEEN SFC HIGH TO OUR EAST AND LOW
PRESSURE TO OUR WEST. THIS WILL PRODUCE BREEZY TO WINDY SOUTHERLY
WINDS. TOWARD THE END OF THE DAY DRYLINE EDGES EAST INTO FAR EASTERN
COLORADO. LOW LEVEL CONVERGENCE ALONG THE DRYLINE COUPLED WITH SOME
WEAK INSTABILITY MAY BE ENOUGH TO PRODUCE SOME ISOLATED
THUNDERSTORMS. FOR NOW HAVE KEPT THEM OUT DURING THE DAY BUT KEPT
THEM IN EARLY TUESDAY NIGHT ACROSS THE FAR EAST. HIGH TEMPERATURES
IN THE MID 70S EAST TO NEAR 80 WEST. LOWS TUESDAY NIGHT GENERALLY IN
THE 50S.
WEDNESDAY...CENTER OF UPPER TROUGH EXPECTED TO MOVE EAST INTO THE
NORTHERN PLAINS WHILE AT THE SFC WINDY/VERY WINDY CONDITIONS
EXPECTED DURING PART/MOST OF THE DAY BEFORE A COLD FRONT MOVES
THROUGH...MOST LIKELY LATE IN THE DAY AND CERTAINLY (AT THIS POINT)
WEDNESDAY NIGHT. A WIND ADVISORY MAY BE NEEDED FOR PARTS OF THE AREA
WHERE GUSTS TO 50 MPH POSSIBLE. INSTABILITY AXIS SETS UP ACROSS THE
FAR EASTERN 1/4 OF THE AREA WHERE CURRENT FORECAST HAS SLIGHT CHANCE
POPS FOR THUNDERSTORMS. SEE NO REASON TO MAKE ADJUSTMENTS TO THIS
THINKING. INSTABILITY AXIS MOVES EAST OF THE AREA WEDNESDAY EVENING
AS COLD FRONT AND WIND SHIFT MOVES IN AND ANY PRECIPITATION CHANCES
LOOK TO BE CONFINED TO THE BEFORE MIDNIGHT PERIOD...CURRENTLY
HANDLED WELL IN CURRENT FORECAST. HIGH TEMPERATURES MID 70S TO
AROUND 80 IN EASTERN COLORADO WITH LOW 80S EAST OF THE CO/KS BORDER.
LOWS WEDNESDAY NIGHT UPPER 30S TO LOW 40S WEST...LOW 40S TO AROUND
50 EAST OF THE CO/KS BORDER.
THURSDAY...UPPER LOW AND ASSOCIATED TROUGH CONTINUE SLOWLY EAST
WHILE SFC FEATURES SHOW NORTHWEST WINDS OVER THE AREA ALONG WITH
COOLER TEMPERATURES. NO PRECIPITATION EXPECTED. HIGH TEMPERATURES
GENERALLY IN THE 60S EXCEPT NEAR 70 BY HILL CITY. LOWS MID TO UPPER
30S WEST...LOW 40S EAST.
FRIDAY...AS UPPER LOW MOVES INTO THE GREAT LAKES WE AWAIT SOME UPPER
RIDGING THAT MOVES IN FRIDAY NIGHT AS ANOTHER STORM SYSTEM MAKES ITS
WAY TOWARD THE PACIFIC NORTHWEST COAST. LOOKS LIKE ANOTHER DRY
PERIOD WITH TEMPERATURES NEAR TO SLIGHTLY ABOVE NORMAL. HIGH
TEMPERATURES GENERALLY IN THE 60S EXCEPT AROUND 70 ACROSS THE FAR
SOUTH. LOWS UPPER 30S WEST TO LOW 40S EAST OF THE CO/KS BORDER.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 531 AM MDT SAT APR 19 2014
TRICKY AND LOW CONFIDENCE WIND AND THUNDERSTORM FORECAST. MODELS
ARE HAVING A HARD HANDLING THE SPEED AND POSITION OF INCOMING
FRONT. THE POSITION OF THE FRONT WILL BE A BIG DETERMINER WHERE
THE THUNDERSTORMS END UP. AT THIS TIME...IT LOOKS LIKE THE BEST
CHANCE FOR THUNDERSTORMS WILL NOT ARRIVE UNTIL THE EVENING AND
ESPECIALLY THE OVERNIGHT HOURS. SO TRENDED THE TAFS IN THAT
DIRECTION. OTHERWISE VFR CONDITIONS ARE EXPECTED THROUGH THE ENTIRE
PERIOD.
&&
.FIRE WEATHER...
ISSUED AT 220 AM MDT SAT APR 19 2014
CRITICAL FIRE WEATHER CONDITIONS ARE POSSIBLE FROM AROUND NOON
MDT (1 PM CDT) WEDNESDAY AFTERNOON THROUGH 7 PM MDT (8 PM CDT)
WEDNESDAY EVENING FOR LOCATIONS GENERALLY ALONG AND WEST OF THE
CO/KS BORDER. IN THIS AREA RELATIVE HUMIDITY IS FORECAST TO DROP
TOWARD 15 PERCENT WITH SOUTHWEST WINDS GUSTING 40 TO 45 MPH.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...024
SHORT TERM...BULLER
LONG TERM...99
AVIATION...BULLER
FIRE WEATHER...99
AREA FORECAST DISCUSSION
NWS GOODLAND KS
536 AM MDT SAT APR 19 2014
.SHORT TERM...(TODAY THROUGH MONDAY NIGHT)
ISSUED AT 341 AM MDT SAT APR 19 2014
FORECAST PROBLEM WILL BE CHANCE OF PRECIPITATION THROUGH THE WEEKEND.
SATELLITE SHOWING AN ACTIVE AND PROGRESSIVE FLOW OVER THE PACIFIC.
THIS TRANSLATES TO A SPLIT FLOW OVER THE COUNTRY WITH A FASTER
NORTHERN STREAM AND A SLOWER/MORE CUTOFF SOUTHERN STREAM. STRONGER
NORTHERN STREAM SYSTEM NOW ALONG THE UNITED STATES/CANADIAN BORDER
IS PUSHING A FRONT TOWARD THE AREA. CLOSED OFF LOW IS OVER SOUTHERN
CALIFORNIA/NORTHERN BAJA. ABOVE MENTIONED COLD FRONT LOOKS TO BE
RAPIDLY APPROACHING THE AREA.
AT JET LEVEL...MODELS NOT DOING THE GREATEST. THE GFS AND CANADIAN
APPEAR TO BE DOING THE BEST WITH THE ECMWF JUST BEHIND THEM. AT MID
LEVELS...ANALYSIS AND SATELLITE SHOW THAT THE CANADIAN IS DOING THE
BEST WITH THE DESERT SOUTHWEST LOW. FOR THE NORTHERN STREAM SYSTEM
THE MODELS TENDED TO NOT HAVE IT FAR ENOUGH SOUTH . HERE THE CANADIAN
WAS DOING A LITTLE BETTER THAN THE GFS. THE MODELS ARE HAVING A VERY
HARD TIME WITH THE SURFACE WIND AND PRESSURE FIELD. THE RUC AND NAM
TENDED TO BE TOO FAR FAST WITH LEE SIDE TROUGH AND ESPECIALLY THE
FRONT. HOWEVER THE OTHER OUTPUT TENDED TO BE TOO SLOW.
VERY COMPLICATED SITUATION AS EVIDENCED BY THE MODEL DIFFERENCES AND
CHANGES IN THE MODEL OUTPUT OVER THE LAST 24 HOURS. CONFIDENCE IS
BELOW AVERAGE IN THE PRECIPITATION FORECAST AND TO SOME DEGREE HOW
THE HIGH TEMPERATURE FORECAST WORK OUT.
TODAY/TONIGHT...MODELS ARE ALL OVER THE PLACE WITH THE SPEED AND
POSITION OF THE FRONT WHICH AFFECTS EVERYTHING ABOUT THE FORECAST.
FASTER MODELS HAVE THE FRONT THROUGH OF THE AREA BY LATE IN THE
AFTERNOON. SOME BRING IT IN FASTER AND THEN SLOW IT/HANG IT UP.
OTHERS STILL ONLY BRING THE FRONT INTO THE NORTHWEST HALF BY LATE
IN THE DAY. TENDED TO GO INTO THE MIDDLE OF THE ROAD.
BLENDING ALL MODEL SOLUTIONS TOGETHER TODAY WOULD SAY THAT
THUNDERSTORMS COULD HAPPEN ABOUT ANYWHERE THIS AFTERNOON. A COUPLE
OF THINGS CONSISTENT FROM YESTERDAY ARE THE MODEL TENDENCIES OF
SLOWING THE SYSTEM DOWN AND HAVING IT MORE CLOSED BY THE TIME IT
MOVES INTO THE AREA TONIGHT. MODELS HAVE BACKED OFF ON THE CHANCE
OF PRECIPITATION FOR TODAY AND THAT SEEMS REASONABLE. CONSIDERING THE
LACK OF SIGNIFICANT LIFT ALOFT AND THE POSSIBILITY OF BEING CAPPED
SUPPORTS THAT. SO REDUCED THE CHANCES FOR THE DAY. DESPITE
DIFFERENCES IN THE FRONTAL POSITION...MODELS DO SHOW IT COMING A
LITTLE FURTHER SOUTH PLUS LOOK TO HAVE A DECENT AMOUNT OF HIGHER
LEVEL CLOUD COVER. SO DID REDUCE MAXES A LITTLE.
MODEL DIFFERENCES CONTINUE TONIGHT. HOWEVER...MODELS DO BRING IN
MUCH BETTER LIFT BUT THEY DIFFER ON WHERE THEY WANT TO PUT IT. TO
COMPLICATE MATTERS IT LOOKS LIKE A FEW OF THE MODELS MAY BE
SUFFERING FROM CONVECTIVE FEEDBACK. DUE TO THE SLOWER TRENDS MODELS
LOOK TO HOLD BACK THE MAIN LIFT UNTIL LATER TONIGHT. ALL THINGS
CONSIDERED KEPT THE POPS IN THE HIGH CHANCE CATEGORY. YESTERDAY
CONCERN WAS THAT LOCALLY HEAVY RAINFALL WOULD BE A PROBLEM. THE
POTENTIAL IS DEFINITELY THERE DUE TO THE HIGH PWATS THAT ARE WAY
ABOVE NORMAL. HOWEVER...DUE TO MODEL DIFFICULTIES HAVING A HARD
SPECIFYING ANY SPECIFIC AREA OR EVEN MENTION IT AT ALL.
SUNDAY/SUNDAY NIGHT...MODELS ARE A LITTLE CLOSER FOR THIS PERIOD
THAN FOR SATURDAY AND SATURDAY NIGHT. SYSTEM IS CLOSED OFF AND NEAR
OR OVER THE WESTERN HALF OF THE AREA AT THE BEGINNING. FRONT HAS
PULLED BACK FURTHER WEST TO NEAR THE COLORADO AND KANSAS BORDER...IF
YOU BELIEVE THE FURTHEST WEST SOLUTION. AS YESTERDAY THE GREATEST
THREAT OF PRECIPITATION IS IN THE EASTERN HALF TO TWO THIRDS WHERE
LOCALLY HEAVY RAINFALL COULD STILL BE A THREAT. PRECIPITATION SHOULD
END DURING THE EVENING. HIGH TEMPERATURES WILL DEPEND ON HOW
EXTENSIVE PRECIPITATION WILL BE. TENDED TO KEEP TEMPERATURES ABOUT
THE SAME IF NOT SLIGHTLY COOLER.
MONDAY/MONDAY NIGHT...SHORTWAVE RIDGING ALOFT MOVES INTO THE AREA AS
NORTHERLY WINDS AT THE SURFACE PUSH IN BEHIND THE EXITING SYSTEM.
ONLY MADE A SLIGHT ADJUSTMENT TO THE MAXES BUT FEEL THAT THE MODELS
MAY BE HAVING THE TEMPERATURES TOO COOL.
.LONG TERM...(TUESDAY THROUGH FRIDAY)
ISSUED AT 220 AM MDT SAT APR 19 2014
TUESDAY...UPPER RIDGE MOVES OVER THE AREA AHEAD OF A LARGE UPPER
TROUGH WHICH BY 12Z WEDNESDAY SHIFTS TOWARD THE NORTHERN
ROCKIES...SHIFTING THE UPPER FLOW TO THE SOUTHWEST. AT THE SFC
INCREASING PRESSURE GRADIENT BETWEEN SFC HIGH TO OUR EAST AND LOW
PRESSURE TO OUR WEST. THIS WILL PRODUCE BREEZY TO WINDY SOUTHERLY
WINDS. TOWARD THE END OF THE DAY DRYLINE EDGES EAST INTO FAR EASTERN
COLORADO. LOW LEVEL CONVERGENCE ALONG THE DRYLINE COUPLED WITH SOME
WEAK INSTABILITY MAY BE ENOUGH TO PRODUCE SOME ISOLATED
THUNDERSTORMS. FOR NOW HAVE KEPT THEM OUT DURING THE DAY BUT KEPT
THEM IN EARLY TUESDAY NIGHT ACROSS THE FAR EAST. HIGH TEMPERATURES
IN THE MID 70S EAST TO NEAR 80 WEST. LOWS TUESDAY NIGHT GENERALLY IN
THE 50S.
WEDNESDAY...CENTER OF UPPER TROUGH EXPECTED TO MOVE EAST INTO THE
NORTHERN PLAINS WHILE AT THE SFC WINDY/VERY WINDY CONDITIONS
EXPECTED DURING PART/MOST OF THE DAY BEFORE A COLD FRONT MOVES
THROUGH...MOST LIKELY LATE IN THE DAY AND CERTAINLY (AT THIS POINT)
WEDNESDAY NIGHT. A WIND ADVISORY MAY BE NEEDED FOR PARTS OF THE AREA
WHERE GUSTS TO 50 MPH POSSIBLE. INSTABILITY AXIS SETS UP ACROSS THE
FAR EASTERN 1/4 OF THE AREA WHERE CURRENT FORECAST HAS SLIGHT CHANCE
POPS FOR THUNDERSTORMS. SEE NO REASON TO MAKE ADJUSTMENTS TO THIS
THINKING. INSTABILITY AXIS MOVES EAST OF THE AREA WEDNESDAY EVENING
AS COLD FRONT AND WIND SHIFT MOVES IN AND ANY PRECIPITATION CHANCES
LOOK TO BE CONFINED TO THE BEFORE MIDNIGHT PERIOD...CURRENTLY
HANDLED WELL IN CURRENT FORECAST. HIGH TEMPERATURES MID 70S TO
AROUND 80 IN EASTERN COLORADO WITH LOW 80S EAST OF THE CO/KS BORDER.
LOWS WEDNESDAY NIGHT UPPER 30S TO LOW 40S WEST...LOW 40S TO AROUND
50 EAST OF THE CO/KS BORDER.
THURSDAY...UPPER LOW AND ASSOCIATED TROUGH CONTINUE SLOWLY EAST
WHILE SFC FEATURES SHOW NORTHWEST WINDS OVER THE AREA ALONG WITH
COOLER TEMPERATURES. NO PRECIPITATION EXPECTED. HIGH TEMPERATURES
GENERALLY IN THE 60S EXCEPT NEAR 70 BY HILL CITY. LOWS MID TO UPPER
30S WEST...LOW 40S EAST.
FRIDAY...AS UPPER LOW MOVES INTO THE GREAT LAKES WE AWAIT SOME UPPER
RIDGING THAT MOVES IN FRIDAY NIGHT AS ANOTHER STORM SYSTEM MAKES ITS
WAY TOWARD THE PACIFIC NORTHWEST COAST. LOOKS LIKE ANOTHER DRY
PERIOD WITH TEMPERATURES NEAR TO SLIGHTLY ABOVE NORMAL. HIGH
TEMPERATURES GENERALLY IN THE 60S EXCEPT AROUND 70 ACROSS THE FAR
SOUTH. LOWS UPPER 30S WEST TO LOW 40S EAST OF THE CO/KS BORDER.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 531 AM MDT SAT APR 19 2014
TRICKY AND LOW CONFIDENCE WIND AND THUNDERSTORM FORECAST. MODELS
ARE HAVING A HARD HANDLING THE SPEED AND POSITION OF INCOMING
FRONT. THE POSITION OF THE FRONT WILL BE A BIG DETERMINER WHERE
THE THUNDERSTORMS END UP. AT THIS TIME...IT LOOKS LIKE THE BEST
CHANCE FOR THUNDERSTORMS WILL NOT ARRIVE UNTIL THE EVENING AND
ESPECIALLY THE OVERNIGHT HOURS. SO TRENDED THE TAFS IN THAT
DIRECTION. OTHERWISE VFR CODNTIONS ARE EXPECTED THROUGH THE ENTIRE
PERIOD.
&&
.FIRE WEATHER...
ISSUED AT 220 AM MDT SAT APR 19 2014
CRITICAL FIRE WEATHER CONDITIONS ARE POSSIBLE FROM AROUND NOON
MDT (1 PM CDT) WEDNESDAY AFTERNOON THROUGH 7 PM MDT (8 PM CDT)
WEDNESDAY EVENING FOR LOCATIONS GENERALLY ALONG AND WEST OF THE
CO/KS BORDER. IN THIS AREA RELATIVE HUMIDITY IS FORECAST TO DROP
TOWARD 15 PERCENT WITH SOUTHWEST WINDS GUSTING 40 TO 45 MPH.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...BULLER
LONG TERM...99
AVIATION...BULLER
FIRE WEATHER...99
AREA FORECAST DISCUSSION...CORRECTION
NWS GOODLAND KS
341 AM MDT SAT APR 19 2014
.SHORT TERM...(TODAY THROUGH MONDAY NIGHT)
ISSUED AT 341 AM MDT SAT APR 19 2014
FORECAST PROBLEM WILL BE CHANCE OF PRECIPITATION THROUGH THE WEEKEND.
SATELLITE SHOWING AN ACTIVE AND PROGRESSIVE FLOW OVER THE PACIFIC.
THIS TRANSLATES TO A SPLIT FLOW OVER THE COUNTRY WITH A FASTER
NORTHERN STREAM AND A SLOWER/MORE CUTOFF SOUTHERN STREAM. STRONGER
NORTHERN STREAM SYSTEM NOW ALONG THE UNITED STATES/CANADIAN BORDER
IS PUSHING A FRONT TOWARD THE AREA. CLOSED OFF LOW IS OVER SOUTHERN
CALIFORNIA/NORTHERN BAJA. ABOVE MENTIONED COLD FRONT LOOKS TO BE
RAPIDLY APPROACHING THE AREA.
AT JET LEVEL...MODELS NOT DOING THE GREATEST. THE GFS AND CANADIAN
APPEAR TO BE DOING THE BEST WITH THE ECMWF JUST BEHIND THEM. AT MID
LEVELS...ANALYSIS AND SATELLITE SHOW THAT THE CANADIAN IS DOING THE
BEST WITH THE DESERT SOUTHWEST LOW. FOR THE NORTHERN STREAM SYSTEM
THE MODELS TENDED TO NOT HAVE IT FAR ENOUGH SOUTH . HERE THE CANADIAN
WAS DOING A LITTLE BETTER THAN THE GFS. THE MODELS ARE HAVING A VERY
HARD TIME WITH THE SURFACE WIND AND PRESSURE FIELD. THE RUC AND NAM
TENDED TO BE TOO FAR FAST WITH LEE SIDE TROUGH AND ESPECIALLY THE
FRONT. HOWEVER THE OTHER OUTPUT TENDED TO BE TOO SLOW.
VERY COMPLICATED SITUATION AS EVIDENCED BY THE MODEL DIFFERENCES AND
CHANGES IN THE MODEL OUTPUT OVER THE LAST 24 HOURS. CONFIDENCE IS
BELOW AVERAGE IN THE PRECIPITATION FORECAST AND TO SOME DEGREE HOW
THE HIGH TEMPERATURE FORECAST WORK OUT.
TODAY/TONIGHT...MODELS ARE ALL OVER THE PLACE WITH THE SPEED AND
POSITION OF THE FRONT WHICH AFFECTS EVERYTHING ABOUT THE FORECAST.
FASTER MODELS HAVE THE FRONT THROUGH OF THE AREA BY LATE IN THE
AFTERNOON. SOME BRING IT IN FASTER AND THEN SLOW IT/HANG IT UP.
OTHERS STILL ONLY BRING THE FRONT INTO THE NORTHWEST HALF BY LATE
IN THE DAY. TENDED TO GO INTO THE MIDDLE OF THE ROAD.
BLENDING ALL MODEL SOLUTIONS TOGETHER TODAY WOULD SAY THAT
THUNDERSTORMS COULD HAPPEN ABOUT ANYWHERE THIS AFTERNOON. A COUPLE
OF THINGS CONSISTENT FROM YESTERDAY ARE THE MODEL TENDENCIES OF
SLOWING THE SYSTEM DOWN AND HAVING IT MORE CLOSED BY THE TIME IT
MOVES INTO THE AREA TONIGHT. MODELS HAVE BACKED OFF ON THE CHANCE
OF PRECIPITATION FOR TODAY AND THAT SEEMS REASONABLE. CONSIDERING THE
LACK OF SIGNIFICANT LIFT ALOFT AND THE POSSIBILITY OF BEING CAPPED
SUPPORTS THAT. SO REDUCED THE CHANCES FOR THE DAY. DESPITE
DIFFERENCES IN THE FRONTAL POSITION...MODELS DO SHOW IT COMING A
LITTLE FURTHER SOUTH PLUS LOOK TO HAVE A DECENT AMOUNT OF HIGHER
LEVEL CLOUD COVER. SO DID REDUCE MAXES A LITTLE.
MODEL DIFFERENCES CONTINUE TONIGHT. HOWEVER...MODELS DO BRING IN
MUCH BETTER LIFT BUT THEY DIFFER ON WHERE THEY WANT TO PUT IT. TO
COMPLICATE MATTERS IT LOOKS LIKE A FEW OF THE MODELS MAY BE
SUFFERING FROM CONVECTIVE FEEDBACK. DUE TO THE SLOWER TRENDS MODELS
LOOK TO HOLD BACK THE MAIN LIFT UNTIL LATER TONIGHT. ALL THINGS
CONSIDERED KEPT THE POPS IN THE HIGH CHANCE CATEGORY. YESTERDAY
CONCERN WAS THAT LOCALLY HEAVY RAINFALL WOULD BE A PROBLEM. THE
POTENTIAL IS DEFINITELY THERE DUE TO THE HIGH PWATS THAT ARE WAY
ABOVE NORMAL. HOWEVER...DUE TO MODEL DIFFICULTIES HAVING A HARD
SPECIFYING ANY SPECIFIC AREA OR EVEN MENTION IT AT ALL.
SUNDAY/SUNDAY NIGHT...MODELS ARE A LITTLE CLOSER FOR THIS PERIOD
THAN FOR SATURDAY AND SATURDAY NIGHT. SYSTEM IS CLOSED OFF AND NEAR
OR OVER THE WESTERN HALF OF THE AREA AT THE BEGINNING. FRONT HAS
PULLED BACK FURTHER WEST TO NEAR THE COLORADO AND KANSAS BORDER...IF
YOU BELIEVE THE FURTHEST WEST SOLUTION. AS YESTERDAY THE GREATEST
THREAT OF PRECIPITATION IS IN THE EASTERN HALF TO TWO THIRDS WHERE
LOCALLY HEAVY RAINFALL COULD STILL BE A THREAT. PRECIPITATION SHOULD
END DURING THE EVENING. HIGH TEMPERATURES WILL DEPEND ON HOW
EXTENSIVE PRECIPITATION WILL BE. TENDED TO KEEP TEMPERATURES ABOUT
THE SAME IF NOT SLIGHTLY COOLER.
MONDAY/MONDAY NIGHT...SHORTWAVE RIDGING ALOFT MOVES INTO THE AREA AS
NORTHERLY WINDS AT THE SURFACE PUSH IN BEHIND THE EXITING SYSTEM.
ONLY MADE A SLIGHT ADJUSTMENT TO THE MAXES BUT FEEL THAT THE MODELS
MAY BE HAVING THE TEMPERATURES TOO COOL.
.LONG TERM...(TUESDAY THROUGH FRIDAY)
ISSUED AT 220 AM MDT SAT APR 19 2014
TUESDAY...UPPER RIDGE MOVES OVER THE AREA AHEAD OF A LARGE UPPER
TROUGH WHICH BY 12Z WEDNESDAY SHIFTS TOWARD THE NORTHERN
ROCKIES...SHIFTING THE UPPER FLOW TO THE SOUTHWEST. AT THE SFC
INCREASING PRESSURE GRADIENT BETWEEN SFC HIGH TO OUR EAST AND LOW
PRESSURE TO OUR WEST. THIS WILL PRODUCE BREEZY TO WINDY SOUTHERLY
WINDS. TOWARD THE END OF THE DAY DRYLINE EDGES EAST INTO FAR EASTERN
COLORADO. LOW LEVEL CONVERGENCE ALONG THE DRYLINE COUPLED WITH SOME
WEAK INSTABILITY MAY BE ENOUGH TO PRODUCE SOME ISOLATED
THUNDERSTORMS. FOR NOW HAVE KEPT THEM OUT DURING THE DAY BUT KEPT
THEM IN EARLY TUESDAY NIGHT ACROSS THE FAR EAST. HIGH TEMPERATURES
IN THE MID 70S EAST TO NEAR 80 WEST. LOWS TUESDAY NIGHT GENERALLY IN
THE 50S.
WEDNESDAY...CENTER OF UPPER TROUGH EXPECTED TO MOVE EAST INTO THE
NORTHERN PLAINS WHILE AT THE SFC WINDY/VERY WINDY CONDITIONS
EXPECTED DURING PART/MOST OF THE DAY BEFORE A COLD FRONT MOVES
THROUGH...MOST LIKELY LATE IN THE DAY AND CERTAINLY (AT THIS POINT)
WEDNESDAY NIGHT. A WIND ADVISORY MAY BE NEEDED FOR PARTS OF THE AREA
WHERE GUSTS TO 50 MPH POSSIBLE. INSTABILITY AXIS SETS UP ACROSS THE
FAR EASTERN 1/4 OF THE AREA WHERE CURRENT FORECAST HAS SLIGHT CHANCE
POPS FOR THUNDERSTORMS. SEE NO REASON TO MAKE ADJUSTMENTS TO THIS
THINKING. INSTABILITY AXIS MOVES EAST OF THE AREA WEDNESDAY EVENING
AS COLD FRONT AND WIND SHIFT MOVES IN AND ANY PRECIPITATION CHANCES
LOOK TO BE CONFINED TO THE BEFORE MIDNIGHT PERIOD...CURRENTLY
HANDLED WELL IN CURRENT FORECAST. HIGH TEMPERATURES MID 70S TO
AROUND 80 IN EASTERN COLORADO WITH LOW 80S EAST OF THE CO/KS BORDER.
LOWS WEDNESDAY NIGHT UPPER 30S TO LOW 40S WEST...LOW 40S TO AROUND
50 EAST OF THE CO/KS BORDER.
THURSDAY...UPPER LOW AND ASSOCIATED TROUGH CONTINUE SLOWLY EAST
WHILE SFC FEATURES SHOW NORTHWEST WINDS OVER THE AREA ALONG WITH
COOLER TEMPERATURES. NO PRECIPITATION EXPECTED. HIGH TEMPERATURES
GENERALLY IN THE 60S EXCEPT NEAR 70 BY HILL CITY. LOWS MID TO UPPER
30S WEST...LOW 40S EAST.
FRIDAY...AS UPPER LOW MOVES INTO THE GREAT LAKES WE AWAIT SOME UPPER
RIDGING THAT MOVES IN FRIDAY NIGHT AS ANOTHER STORM SYSTEM MAKES ITS
WAY TOWARD THE PACIFIC NORTHWEST COAST. LOOKS LIKE ANOTHER DRY
PERIOD WITH TEMPERATURES NEAR TO SLIGHTLY ABOVE NORMAL. HIGH
TEMPERATURES GENERALLY IN THE 60S EXCEPT AROUND 70 ACROSS THE FAR
SOUTH. LOWS UPPER 30S WEST TO LOW 40S EAST OF THE CO/KS BORDER.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1037 PM MDT FRI APR 18 2014
VFR CONDITIONS ARE EXPECTED THROUGH THE TAF PERIOD AT MCK AND
GLD. GUSTY SOUTH WINDS WILL TURN TO THE NORTH NORTHEAST AFTER 15Z
WITH THE PASSAGE OF A COLD FRONT. HIGH CLOUDS WILL INCREASE
THROUGH THE REMAINDER OF TONIGHT WITH CEILINGS LOWERING THROUGH
THE DAY ON SATURDAY AS THE FRONT APPROACHES. EXPECT SCATTERED
THUNDERSTORMS TO DEVELOP AFTER 20Z AND BECOME MORE WIDESPREAD
AFTER 03Z.
&&
.FIRE WEATHER...
ISSUED AT 220 AM MDT SAT APR 19 2014
CRITICAL FIRE WEATHER CONDITIONS ARE POSSIBLE FROM AROUND NOON
MDT (1 PM CDT) WEDNESDAY AFTERNOON THROUGH 7 PM MDT (8 PM CDT)
WEDNESDAY EVENING FOR LOCATIONS GENERALLY ALONG AND WEST OF THE
CO/KS BORDER. IN THIS AREA RELATIVE HUMIDITY IS FORECAST TO DROP
TOWARD 15 PERCENT WITH SOUTHWEST WINDS GUSTING 40 TO 45 MPH.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...BULLER
LONG TERM...99
AVIATION...LOCKHART
FIRE WEATHER...99
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
321 PM CDT SAT APR 19 2014
.SHORT TERM...(TONIGHT THROUGH TUESDAY)
ISSUED AT 309 PM CDT SAT APR 19 2014
RAIN/THUNDERSTORM CHANCES THROUGH MONDAY MORNING ARE THE PRIMARY
FORECAST CONCERNS.
FRONTAL BOUNDARY HAS SLIPPED INTO NORTHEAST NEBRASKA THIS AFTERNOON.
AHEAD OF THE FRONT...TEMPERATURES HAVE CLIMBED WELL INTO THE 70S ON
BRISK SOUTH TO SOUTHWEST WINDS...HOWEVER MOISTURE HAS BEEN SLOW TO
RETURN. DEW POINTS WERE GENERALLY IN THE MID AND UPPER 40S...WITH
LOWER 50S READINGS WELL SOUTH IN CENTRAL KANSAS AND OKLAHOMA. A
WEAK MID LEVEL WAVE AS SEEN IN WATER VAPOR IMAGERY AND RAP HEIGHT
FIELDS WAS MOVING THROUGH NORTHEAST NEBRASKA...AND WAS TRIGGERING
MID LEVEL RETURNS ON RADAR ACROSS NORTHEAST NEBRASKA AND EASTERN
SOUTH DAKOTA. HOWEVER ONLY VIRGA IS EXPECTED THERE AS LOW
HUMIDITIES EXIST BELOW MID LEVEL CLOUD LAYER. CONGESTUS CLOUDS
WERE ALSO NOTED IN SOUTH CENTRAL NEBRASKA IN AREA OF INCREASING
BUT STILL WEAK INSTABILITY.
MEANWHILE...UPPER TROUGH DRIFTING EAST THROUGH ARIZONA WILL
GRADUALLY WORK TOWARD THE PLAINS OVERNIGHT AND EVENTUALLY EAST OF
THE AREA MONDAY. AHEAD OF THIS TROUGH...A COUPLE OF MID LEVEL WAVES
WILL RIPPLE NORTHEAST ACROSS NEBRASKA...AND SHOULD TRIGGER
SCATTERED SHOWERS OR STORMS FOCUSED NEAR SURFACE FRONT. BEST
CHANCE FOR THUNDERSTORMS APPEARS TO COME LATER THIS EVENING AND
OVERNIGHT AS CONVECTION EXPECTED TO DEVELOP IN NORTH CENTRAL
KANSAS OR SOUTH CENTRAL NEBRASKA MOVES INTO OUR AREA. THE SLOW
MOISTURE RETURN WAS HOLDING INSTABILITY IN CHECK THIS AFTERNOON
BUT IS EXPECTED TO INCREASE LATE IN THE DAY OR EARLY EVENING. MID
LEVEL LAPSE RATES OF 8.5-9 C/KM WERE ALREADY IN PLACE IN WESTERN
KANSAS/NEBRASKA OVER TOP OF INCREASING LOW LEVEL CONVERGENCE
NORTHEAST OF SURFACE LOW IN EASTERN COLORADO. VARIOUS SYNOPTIC AND
MESO SCALE MODELS (NAM/GFS/RAP/HRRR/HOPWRF) INDICATE CONVECTION
POPPING IN NORTH CENTRAL KANSAS AND SOUTH CENTRAL NEBRASKA
SOMETIME IN THE 23Z TO 02Z TIMEFRAME...AND DEVELOP/SPREAD THIS
NORTHEAST ALONG FRONTAL ZONE DURING THE EVENING. SEVERE PARAMETERS
ARE NOT IMPRESSIVE WHEN STORMS ARRIVE OVERNIGHT...ELEVATED CAPE
800 J/KG AND 0-6KM SHEAR NEAR 25KT...SO NOT EXPECTING MORE THAN
SMALL HAIL AND GUSTY WINDS. CHANCES WILL DECREASE FROM SOUTHWEST
TO NORTHEAST AFTER MIDNIGHT AS THIS COMPLEX ROLLS OUT OF OUR AREA.
THEN CHANCES BEGIN TO INCREASE AGAIN SUNDAY MORNING WITH THE
APPROACH OF UPPER TROUGH. SURFACE DEW POINTS WILL CONTINUE TO
RISE...LIKELY INTO THE MID TO UPPER 50S BY AFTERNOON...WITH COLD
FRONT BRIDGING NORTH TOWARD THE SOUTH DAKOTA BORDER. AFTERNOON
SURFACE CAPES SHOULD APPROACH 1500 J/KG BUT SHEAR IS LIMITED. SO
AGAIN SEVERE CHANCES ARE SMALL...BUT CONTINUED DEVELOPMENT OF
SHOWERS/STORMS APPEARS LIKELY THROUGH THE AFTERNOON AND EVENING
GIVEN COOLING ALOFT FROM UPPER TROUGH. WILL HAVE FAIRLY HIGH PRECIP
CHANCES SUNDAY AFTERNOON AND NIGHT FOR MUCH OF THE SOUTHERN TWO-
THIRDS OF THE CWA BEFORE FRONT FINALLY BEGINS MOVING SOUTHEAST LATE
SUNDAY NIGHT. LINGERING SHOWERS/STORMS NEAR I-80 AND SOUTH WILL
REMAIN IN THE FORECAST MONDAY MORNING...THEN CLEARING SKIES WITH
SURFACE HIGH PRESSURE AND RIDGING ALOFT BUILDING IN WILL RULE THE
FORECAST INTO TUESDAY.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 309 PM CDT SAT APR 19 2014
THE LONGER TERM PERIOD WILL BEGIN WITH UPPER RIDGE AXIS SHIFTING OFF
TO THE EAST WITH THE APPROACH OF ANOTHER TROUGH SLIDING INTO THE
ROCKIES. THAT TROUGH WILL WORK THROUGH THE PLAINS WEDNESDAY AND
THURSDAY BEFORE LIFTING THROUGH THE GREAT LAKES FRIDAY AND SATURDAY.
WILL HAVE PRECIPITATION CHANCES IN THE FORECAST UNTIL THAT PASSES
BY...WITH A CHANCE FOR SEVERE STORMS AT MID WEEK.
THUNDERSTORMS ARE POSSIBLE TUESDAY NIGHT AS WARM ADVECTION COMMENCES
UNDER DIFFLUENT MID LEVEL FLOW AHEAD OF WESTERN TROUGH. MID LEVEL
INSTABILITY IS NOT THAT STRONG THEN...BUT SCATTERED SHOWERS/STORMS
ARE CERTAINLY POSSIBLE. ON WEDNESDAY...SURFACE LOW PRESSURE WILL
INTENSIFY IN THE HIGH PLAINS WITH DRYLINE SETTING UP IN WESTERN
NEBRASKA. WARM ADVECTION CONTINUES OVER OUR AREA LEADING TO
LINGERING CHANCE FOR SHOWERS/STORMS. BUT BETTER CHANCES COME
WEDNESDAY NIGHT AS LOW/FRONT/DRYLINE MOVE INTO EASTERN NEBRASKA
UNDER DYNAMIC MID LEVEL FLOW AND 60KT LOW LEVEL JET. TIMING AND
MAGNITUDE OF THESE FEATURES WILL STILL HAVE TO BE FINE-TUNED WITH
LATER FORECASTS...BUT THIS CERTAINLY BEARS WATCHING.
MOST OF THE THUNDERSTORM ACTIVITY WILL BE EXITING THURSDAY
MORNING...BUT COULD SEE SOME REDEVELOPMENT OF SHOWERS ESPECIALLY IN
OUR NORTH AND EAST DURING THE AFTERNOON AS MID LEVEL COLD POOL
ROTATES THROUGH THE REGION. COOLER AIR WILL FOLLOW WITH HIGHS
GENERALLY IN THE 60S TO END THE WEEK.
&&
.AVIATION...(18Z TAFS FOR KOFK...KLNK AND KOMA.)
ISSUED AT 1246 PM CDT SAT APR 19 2014
VFR CONDITIONS ARE EXPECTED THROUGH THIS AFTERNOON. A COLD FRONT
WILL CONTINUE TO SLOWLY MOVE SOUTHEAST ACROSS THE AREA. MVFR CIGS
AND VISIBILITIES ARE POSSIBLE FOR THE REMAINDER OF THE TAF PERIOD
AS THE COLD FRONT BEGINS TO STALL. THE FRONT WILL BE THE FOCUS FOR
SHOWERS...ESPECIALLY FROM NEAR 02-10Z AND AGAIN AT KOFK FROM
12-18Z SUN. MORE SHOWERS AND POTENTIAL THUNDERSTORMS ARE POSSIBLE
FOR KLNK AND KOMA AFTER 18Z SUNDAY.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SHORT TERM...DERGAN
LONG TERM...DERGAN
AVIATION...KERN
AREA FORECAST DISCUSSION
NWS ALBUQUERQUE NM
218 PM MDT SAT APR 19 2014
.SYNOPSIS...
SHOWERS AND A FEW THUNDERSTORMS WILL DEVELOP OVER THE REGION TONIGHT
AND BECOME MORE WIDESPREAD SATURDAY AND SUNDAY. THE GREATEST POTENTIAL
FOR MODERATE RAINFALL AMOUNTS WILL FOCUS MAINLY SOUTH OF INTERSTATE
40. A FEW SHOWERS AND THUNDERSTORMS MAY BECOME LOCALLY STRONG BOTH
SATURDAY AND SUNDAY FOR THE SOUTHEASTERN PLAINS. ANY SHOWER ACTIVITY
WILL BE CAPABLE OF PRODUCING STRONG GUSTY WINDS AND BLOWING DUST.
TEMPERATURES WILL COOL TO NEAR NORMAL THROUGH THIS PERIOD. DRYING
AND WARMING WILL COMMENCE MONDAY BEFORE WARMER TEMPERATURES AND THE
SPRING WINDS RETURN FOR MUCH OF THE REMAINDER OF NEXT WEEK.
&&
.DISCUSSION...
ABUNDANT MOISTURE HAS FINALLY RETURNED TO NM TODAY. CIRA PERCENT
OF NORMAL PWAT VALUES ARE WELL ABOVE NORMAL FOR A LARGE AREA OF
THE STATE. THE 12Z KABQ RAOB PWAT OF 0.54 WAS +2 STD DEV ABV CLIMO
AND 0.77 AT KEPZ WAS AT THE 99TH PERCENTILE. THE WATER VAPOR LOOP
SHOWS A LARGE SCALE UPPER LOW DRAGGING ALL THIS MOISTURE INTO THE
AREA AND SHIFTING VERY SLOWLY EAST ACROSS NM/SOUTHERN AZ. THICK
CLOUD COVER OVER CENTRAL NM HAS REALLY HAMPERED TRANSLATION AND
DEVELOPMENT OF PRECIP INTO THE REGION...WHILE NUMEROUS SHRA/TSRA
IMPACT NEARLY THE ENTIRE PERIPHERY. FORTUNATELY AREAS THAT HAVE
REPORTED PRECIP SINCE MIDNIGHT ARE DOING QUITE WELL. LOTS OF 0.25
TO 0.50 INCH REPORTS GENERALLY ALONG AND SOUTH OF HIGHWAY 60.
UNFORTUNATELY MODEL AGREEMENT IS NOT GREAT TONIGHT INTO SUNDAY WITH
THE FOCUS FOR HIGHEST CHANCES. THE LATEST HRRR CONTINUES TO INDICATE
A TROWAL FEATURE DEVELOPING OVER THE CENTRAL MT CHAIN AND RIO GRANDE
VALLEY TONIGHT AS THE UPPER TROUGH SHIFTS INTO EASTERN NM. QPF
NUMBERS COULD BE IMPRESSIVE FOR THE CENTRAL MTS/VALLEY IF IN FACT
THIS FEATURE DEVELOPS. OTHER OPERATIONAL GUIDANCE SHOWS THIS TO
SOME DEGREE BUT CONVECTIVE QPF BULLSEYES ARE ALL OVER THE PLACE.
DIDNT CHANGE GRIDS TOO MUCH FOR TONIGHT SINCE CONFIDENCE ON THE
PLACEMENT OF DEFINITE POPS IS TOO LOW. THE MAIN FORCING WILL SLIDE
INTO THE NE PLAINS SUNDAY WHERE A SURFACE FRONT ALSO SLIPS INTO
THE REGION. INCREASED POPS A TAD THERE AND LOWERED FOR THE WEST
WHERE DRIER AIR SHOULD BEGIN FILTERING INTO THE AREA.
DID NOT FOCUS MUCH ON THE MONDAY THROUGH FRIDAY PERIOD SINCE MAINLY A
TEMPERATURE AND WIND FORECAST. PRECIP CHANCES WILL LOWER AS VERY DRY
AIR BEGINS SCOURING OUT ANY LOW LEVEL MOISTURE LEFT OVER FROM THE
CURRENT SYSTEM. TUESDAY AND WEDNESDAY LOOK NASTY WITH STRONG WINDS...
BLOWING DUST...AND CRITICAL FIRE WEATHER CONDITIONS.
GUYER
&&
.FIRE WEATHER...
CRITICAL FIRE WEATHER OUTLOOK...CRITICAL FIRE WEATHER SETTING UP FOR
NORTHWEST PLATEAU AND ADJACENT HIGHLANDS TUESDAY AFTERNOON...AND
ACROSS MUCH OF THE STATE WEDNESDAY. CRITICAL CONDITIONS
REDEVELOPING OVER THE EASTERN PLAINS THURSDAY...AND AGAIN ON SUNDAY.
MODELS...IN REASONABLE AGREEMENT THROUGH THE UPCOMING WORK WEEK AND
WEEKEND...WITH SOME DIFFERENCES IN STRENGTH AND TIMING OF FEATURES
EARLY IN THE FOLLOWING WORK WEEK. BROAD TROUGH FROM SALT LAKE CITY
ACROSS ARIZONA TO THE GULF OF CALIFORNIA WILL DRIFT EAST ACROSS NEW
MEXICO THROUGH THE REMAINDER OF THE WEEKEND AS UPSTREAM RIDGE SLIDES
OVER THE STATE MONDAY. TROUGH DIGGING OUT OF THE NORTHEAST PACIFIC
OCEAN WILL SWING ONSHORE CENTRAL CALIFORNIA EARLY TUESDAY..TILT
NEGATIVE...AND THEN MOVE TO THE FOUR CORNERS ON WEDNESDAY. TROUGH
WILL SHEAR RAPIDLY ACROSS THE STATE INTO THURSDAY MORNING LEAVING
STATE IN ZONAL FLOW. NEXT PACIFIC TROUGH WILL ARRIVE OVER THE
CALIFORNIA COAST IN NEGATIVE TILT ASPECT SATURDAY MORNING...AND THIS
FEATURE WILL MOVE ACROSS THE STATE OVER THE WEEKEND. MONDAY MORNING
DAWNS WITH DIFFERENCES EMERGING IN DISPLAYED FEATURES BETWEEN
SOLUTIONS. EUROPEAN ECMWF MAINTAINS A BRISK SHEARING ZONAL TO
NORTHWEST FLOW ACROSS THE STATE INTO THE FIRST OF THE WORK
WEEK...WHILE GFS OPTS FOR CLOSING THE TROUGH OFF INTO A CLOSED LOW
OVER COLORADO AND NORTHERN NEW MEXICO...WITH CORRESPONDINGLY SLOW
EJECTION INTO THE CENTRAL PLAINS. GFS TENDENCIES TO CLOSE FEATURES
OFF OVER THE WEST OF LATE ARE BECOMING EVIDENT...AND WILL THUS OPT
FOR THE MORE SHEARED AND PROGRESSIVE ECMWF SOLUTION TO GUIDE
EXTENDED FORECAST THINKING FOR NOW PENDING BETTER AGREEMENT.
OVERNIGHT...A TEMPERATURE REPEAT OF LAST NIGHT IN A CLOUDY AND
SHOWERY PERIOD WITH THUNDERSTORMS RUNNING PRETTY MUCH ALL NIGHT.
SHOWER FOCUS WILL SHIFT TO THE EASTERN PLAINS BY SUNRISE. GOOD TO
EXCELLENT HUMIDITY RECOVERIES...AND GUSTS LIMITED TO THE PROXIMITY
OF THUNDERSTORMS WITH OTHERWISE WEAK WINDS OVERHEAD AND NEAR THE
SURFACE.
FOR SUNDAY...BAGGY TROUGH OVER EASTERN NEW MEXICO BY DAYBREAK WILL
DRIFT OFF INTO TEXAS AND THE SOUTHERN PLAINS STATES BY LATE SUNDAY
AFTERNOON. SHOWER FOCUS WILL TRAIL THE SYSTEM...WITH SHOWER FOCUS
MAINLY NORTH AND NORTHEAST...AND SHOWERS TAPERING OVER THE EAST.
ISOLATED COVERAGE WILL HANG IN THERE THROUGH SUNDAY AFTERNOON OVER
THE WEST. MOISTURE INFLUX WILL KEEP MINIMUM HUMIDITIES IN THE 30S
PCT OVER THE EAST...AND IN THE 20S PCT OVER THE EAST IN MODEST WEST
TO NORTHWEST WINDS IN THE WAKE OF THE DEPARTING TROUGH. GENERALLY
GOOD OR BETTER VENTILATION CONDITIONS THROUGH THE DAY WITH GOOD TO
EXCELLENT HUMIDITY RECOVERIES OVERNIGHT. DAYTIME TEMPERATURES CLOSE
TO LATE APRIL NORMALS.
FOR MONDAY...RIDGE BUILDS OVER NEW MEXICO WITH LIGHT WINDS ALOFT AND
AT THE SURFACE. SPOTTY SHOWER COVERAGE LINGERING OVER THE EAST WILL
END OVER THE NORTHEAST MONDAY NIGHT WITH MODEST RAINFALLS...AS COOL
PUSH FROM THE NORTHEAST CROSSES INTO NEW MEXICO AND SLOPS OVER THE
CENTRAL MOUNTAIN CHAIN AND RIO GRANDE OUT TO THE CONTINENTAL DIVIDE
BY MONDAY NIGHT. DRYING TREND WILL DROP MINIMUM HUMIDITIES INTO THE
UPPER TEENS PCT OVER THE WEST...AND THE 20S PCT OVER THE EAST.
VENTILATION CONDITIONS MOVING DOWN GRADUALLY...WITH FAIR OR BETTER
CONDITIONS...BEST IN THE EXTREME EAST. GENERALLY GOOD HUMIDITY
RECOVERIES OVERNIGHT.
FOR TUESDAY...DRYING OUT AND WARMING UP...AS DAYTIME HIGH
TEMPERATURES RISE TO 3 TO 8 DEGREES ABOVE NORMAL...AND RIDGE AXIS
CROSSES THE HEART OF THE STATE THROUGH TUESDAY AFTERNOON IN ADVANCE
OF SUBSTANTIAL WEST COAST TROUGH. SURFACE WINDS WILL VEER SOUTHERLY
AS SURFACE LOW DEEPENS OVER THE NEW MEXICO BOOT HEEL. GUSTS NEAR THE
ARIZONA BORDER AND HUMIDITIES IN THE LOW TEENS PCT WILL SPREAD SOME
CRITICAL FIRE POTENTIAL ACROSS THE CHUSKA MOUNTAINS AND ADJACENT
NORTHWEST PLATEAU TUESDAY AFTERNOON...AS ABOVE NORMAL TEMPERATURES
AND HAINES INDICES RUNNING AROUND 5 IN THE AREA CONTRIBUTE TO THE
OVERALL THREAT PICTURE...AND THIS WILL BEAR WATCHING CAREFULLY.
ELSEWHERE...HUMIDITIES IN THE 20S PCT EAST WITH FAIR TO GOOD
HUMIDITY RECOVERIES STATEWIDE TUESDAY NIGHT. NO VENTILATION ISSUES.
OUTLOOK...WEDNESDAY THROUGH FRIDAY...WEST COAST TROUGH MOVING TO THE
FOUR CORNERS WEDNESDAY FOR A WINDY SLIDE ACROSS THE STATE THROUGH
THURSDAY. TRAILING RIDGE WILL MOVE IN ON FRIDAY AS WIND SPEEDS DIE
DOWN. TEMPERATURES RUNNING AT LATE APRIL NORMALS OR A FEW DEGREES
ABOVE IN A VERY DRY ENDING TO THE WORK WEEK. WINDY WEDNESDAY
COMBINED WITH SINGLE DIGIT HUMIDITIES WILL PRODUCE WIDESPREAD
CRITICAL FIRE WEATHER CONDITIONS OVER MUCH OF THE STATE...AS
THURSDAY GUSTS OVER THE EAST REDEVELOP THE CRITICAL PATTERN ALONG
AND SOUTH OF THE INTERSTATE 40 CORRIDOR FROM THE RIO GRANDE TO THE
TEXAS LINE. REDUCED WIND SPEEDS FRIDAY WILL EASE UP ON THE FIRE
WEATHER PATTERN TO END THE WORK WEEK. NO VENTILATION ISSUES
WEDNESDAY AND FRIDAY...CONDITIONS RUNNING GOOD OR BETTER ON THE
INTERVENING THURSDAY. POOR TO FAIR HUMIDITY RECOVERIES ALL THREE
NIGHTS.
SHY
&&
.AVIATION...
18Z TAF CYCLE
CONVECTIVELY ACTIVE AFTERNOON UNDERWAY AS TROUGH FROM SALT LAKE
CITY ACROSS ARIZONA TO THE NORTHERN GULF OF CALIFORNIA IS SLUICING
MOISTURE AND ENERGY NORTHWARD ACROSS NEW MEXICO. THUNDERSTORMS
INITIATING ACROSS SOUTHERN HALF OF NM WILL MOVE NORTH THROUGH THE
EVENING...WITH SIGNIFICANT STORM REDEVELOPMENT TOWARD 05Z THIS
EVENING AS TROUGH AXIS SWINGS DIRECTLY OVER THE HEART OF NM.
INITIAL REDEVELOPMENT OVER THE CONTINENTAL DIVIDE WILL SLIDE TO
THE RIO GRANDE VALLEY...AN THEN WIND UP OVER THE CENTRAL MT CHAIN
BY 12Z SUN MORNING. TROUGH AXIS WILL APPROACH THE TX STATE LINE
HEADING EAST WITH THE LAST OF THE OVERNIGHT CONVECTION TAPERING
DOWN BY 18Z SUN NOON. FOR TAFS...VCTS SIGNALING WINDOW OF GREATEST
LIKELIHOOD OF NEARBY THUNDERSTORMS...WITH VCSH SIGNALING CONTINUED
SHOWERS AND THUNDERSTORMS NEAR TERMINALS AT REDUCED INTENSITY.
SHY
&&
.PRELIMINARY POINT TEMPS/POPS...
FARMINGTON...................... 42 74 41 77 / 10 20 10 0
DULCE........................... 34 69 31 71 / 30 30 10 10
CUBA............................ 35 68 35 70 / 50 30 10 10
GALLUP.......................... 35 72 34 76 / 20 20 10 0
EL MORRO........................ 29 64 30 68 / 40 20 10 5
GRANTS.......................... 35 69 35 72 / 30 20 10 5
QUEMADO......................... 37 66 40 70 / 50 20 10 5
GLENWOOD........................ 36 74 36 79 / 30 10 5 0
CHAMA........................... 35 62 31 65 / 40 60 20 20
LOS ALAMOS...................... 45 65 45 68 / 50 40 10 20
PECOS........................... 42 61 41 63 / 70 40 20 20
CERRO/QUESTA.................... 35 65 32 68 / 40 60 20 20
RED RIVER....................... 33 51 31 53 / 60 70 30 40
ANGEL FIRE...................... 33 55 30 58 / 60 70 20 30
TAOS............................ 36 65 33 68 / 40 40 10 20
MORA............................ 41 62 39 63 / 60 50 20 30
ESPANOLA........................ 39 71 37 74 / 40 30 10 10
SANTA FE........................ 43 63 43 66 / 50 40 10 10
SANTA FE AIRPORT................ 39 69 39 72 / 50 30 10 10
ALBUQUERQUE FOOTHILLS........... 48 72 50 75 / 50 20 10 5
ALBUQUERQUE HEIGHTS............. 49 74 49 76 / 50 20 5 5
ALBUQUERQUE VALLEY.............. 45 76 44 78 / 40 20 5 5
ALBUQUERQUE WEST MESA........... 48 77 47 79 / 40 20 5 5
LOS LUNAS....................... 44 77 42 80 / 40 20 5 5
RIO RANCHO...................... 47 76 47 78 / 40 20 5 5
SOCORRO......................... 51 78 51 81 / 50 20 5 5
SANDIA PARK/CEDAR CREST......... 45 68 45 70 / 70 30 10 10
TIJERAS......................... 46 69 47 71 / 60 30 10 10
MORIARTY/ESTANCIA............... 37 67 36 69 / 70 30 10 10
CLINES CORNERS.................. 41 65 41 67 / 70 30 10 10
GRAN QUIVIRA.................... 44 68 46 71 / 60 30 10 10
CARRIZOZO....................... 47 70 46 74 / 50 20 5 10
RUIDOSO......................... 42 65 42 67 / 60 30 10 20
CAPULIN......................... 44 60 42 61 / 60 70 20 20
RATON........................... 42 65 40 67 / 60 50 20 20
SPRINGER........................ 45 66 42 68 / 60 40 20 20
LAS VEGAS....................... 42 65 41 67 / 60 40 20 20
CLAYTON......................... 52 69 51 69 / 50 50 10 20
ROY............................. 48 65 45 67 / 50 40 20 20
CONCHAS......................... 52 73 50 74 / 40 40 10 10
SANTA ROSA...................... 51 73 48 74 / 40 30 10 10
TUCUMCARI....................... 54 76 52 77 / 40 30 10 20
CLOVIS.......................... 49 74 48 76 / 60 30 10 10
PORTALES........................ 51 75 49 76 / 60 30 10 10
FORT SUMNER..................... 53 76 51 77 / 50 30 10 10
ROSWELL......................... 52 80 51 81 / 60 20 10 10
PICACHO......................... 49 74 48 76 / 60 20 10 20
ELK............................. 46 69 47 70 / 60 20 10 20
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
1127 PM MDT FRI APR 18 2014
.AVIATION...
06Z TAF CYCLE
WEAK SHOWERS AND VIRGA WILL CONTINUE STREAMING NORTH AND EAST
THROUGH CENTRAL NM DURING THE EARLY MORNING HOURS. EXPECT PERIODS
OF GUSTY WINDS MIXED WITH LIGHT RAIN...AS WELL AS OCCASIONAL MTN
OBSCURATIONS. EXPECT PRECIP AT TERMINAL SITES TO BE SHORT
LIVED. BASED ON RADAR TRENDS...WENT WITH TEMPO GROUPS FOR
KABQ...KAEG...AND KSAF WITH ONLY A MENTION OF VCSH AT
KFMN...KGUP...AND KROW. MORE WIDESPREAD SHRA AND TSTMS WILL
DEVELOP SATURDAY AFTN AND POTENTIALLY IMPACT ALL SITES. VFR
CONDITIONS WILL PREVAIL...THOUGH A STORM COULD BRIEFLY BRING A
SITE DOWN TO MVFR CIGS. DUE TO SPOTTY NATURE OF SHRA AND
TSTMS...CONFIDENCE TOO LOW FOR MENTION OF ANYTHING MORE THAN VCSH.
SOUTHERLY TO SOUTHWESTERLY FLOW WILL BE STRONGEST ALONG AND EAST
OF CENTRAL MTS...GUSTING UP TO 35 MPH.
24
&&
.PREV DISCUSSION...300 PM MDT FRI APR 18 2014...
.SYNOPSIS...
SHOWERS AND A FEW THUNDERSTORMS WILL DEVELOP OVER THE REGION TONIGHT
AND BECOME MORE WIDESPREAD SATURDAY AND SUNDAY. THE GREATEST POTENTIAL
FOR MODERATE RAINFALL AMOUNTS WILL FOCUS MAINLY SOUTH OF INTERSTATE
40. A FEW SHOWERS AND THUNDERSTORMS MAY BECOME LOCALLY STRONG BOTH
SATURDAY AND SUNDAY FOR THE SOUTHEASTERN PLAINS. ANY SHOWER ACTIVITY
WILL BE CAPABLE OF PRODUCING STRONG GUSTY WINDS AND BLOWING DUST.
TEMPERATURES WILL COOL TO NEAR NORMAL THROUGH THIS PERIOD. DRYING
AND WARMING WILL COMMENCE MONDAY BEFORE WARMER TEMPERATURES AND THE
SPRING WINDS RETURN FOR MUCH OF THE REMAINDER OF NEXT WEEK.
&&
.DISCUSSION...
LATEST CIRA BLENDED PWAT LOOP INDICATES A WIDESPREAD AREA OF THE
DESERT SW UNDER STRONG MOIST ADVECTION TODAY. PCT OF NORMAL VALUES
IN THIS MOIST PLUME HAVE INCREASED TO BTWN 100-150 PCT OF NORMAL
WITH POCKETS OF GREATER THAN 200 PCT. SATELLITE SHOWS THE ASSOCIATED
UPPER LEVEL STORM SYSTEM PUSHING SLOWLY EAST WHILE THE CENTER OF
CIRCULATION WEAKENS OVER SOUTHERN CALIFORNIA. 12Z-18Z GUIDANCE IS
IN GOOD AGREEMENT WITH THE OVERALL TIMING AND PLACEMENT OF MOIST
INSTABILITY OVER OUR REGION THROUGH SUNDAY. THE 16Z HRRR WAS VERY
BULLISH ON DEVELOPING A LARGE AREA OF RAIN/STORMS OVER THE SW MTS
THIS EVENING THEN SLIDING NORTH ALONG THE CONT DVD INTO SAN JUAN
COUNTY...WITH ANOTHER BULLSEYE FROM LINCOLN AND CHAVES COUNTIES INTO
THE SE PLAINS. TRENDED POPS UP FOR THESE AREAS BUT VERY DRY LOW
LEVELS WILL BATTLE THE INITIAL DEVELOPMENT FOR SEVERAL HOURS BEFORE
TOP DOWN EFFECTS TAKE OVER.
MODEL INSTABILITY PARAMETERS ARE PROBABLY THE STRONGEST SO FAR THIS
SPRING SEASON FOR MUCH OF THE SOUTH AND EAST. LIFTED INDICES MAY
AVERAGE -2 TO -3C WTIH CAPE OF 500-800 J/KG. SHEAR VALUES ARE WEAK
SO MAIN THREAT WILL BE STRONG WINDS AND BLOWING DUST WITH SMALL HAIL
POSSIBLE. ALSO RAISED POP VALUES FOR THIS PERIOD IN LINE WITH HPC
PROBABILISTIC QPF GUIDANCE. DRY AIR WILL BEGIN SHIFTING IN FROM THE
WEST SUNDAY WITH THE MAIN UPPER FORCING. THIS WILL CREATE A STRONGER
FOCUS FOR STRONG STORMS OVER THE SE PLAINS BUT COVERAGE SHOULD BE
MORE LIMITED FOR CENTRAL AND WESTERN NM. MAX TEMPS THRU THE PERIOD
WILL BE NEAR NORMAL WHILE MIN TEMPS REMAIN QUITE WARM.
MONDAY WILL BE A TRANSITION DAY WITH TEMPS WARMING AND DRY AIR
SCOURING OUT ANY REMAINING LOW LEVEL MOISTURE. WINDS WILL RETURN
TUESDAY THROUGH THE REMAINDER OF THE WEEK. DEFINITELY WATCHING
CLOSELY FOR ANY FIRE STARTS FROM DRY STORM ACTIVITY THE NEXT COUPLE
DAYS SINCE THE WINDS LOOK UGLY FOR AN EXTENDED DURATION THEREAFTER.
GUYER
&&
.FIRE WEATHER...
LIGHTNING SLOW TO APPROACH STATE BUT LOOK FOR IT LATER TODAY INTO
THE OVERNIGHT AS THE ATMOSPHERE DESTABILIZES. WETTING STORMS ON
SATURDAY WITH RESIDUAL IMPACTS SUNDAY ALTHOUGH DRIER. CONFIDENCE
HIGH FOR A MULTI DAY WIND EVENT STARTING TUESDAY AND LASTING INTO
THURSDAY. MODELS HAVE SLOWED THE TROUGH FOR TUESDAY WHICH MEANS
CRITICAL CONDITIONS SHIFT FURTHER TO THE WEST. WEDNESDAY LOOKS TO
BE A DOOZY WITH LOW TO VERY LOW RH COMBINED WITH REALLY STRONG
WIND AREAWIDE. POST COLD FRONTAL CONDITIONS MOST AREAS ON THURSDAY
WITH RESIDUAL STRONG WIND. STRONG WIND/LOW RH ACROSS THE EASTERN
HALF THURSDAY.
AS FAR AS THE REST OF TODAY. CLOUDS WILL OVERSPREAD THE AREA. THE
HIGHER CIRRUS HAS KEPT SURFACE BASED CONVECTION FROM DEVELOPING BUT
THE RIGHT COMBINATION OF INSTABILITY AND MOISTURE IS QUICKLY
APPROACHING FROM EAST CENTRAL AND SOUTHEAST ARIZONA. MAINLY ISOLATED
THUNDERSTORMS...INITIALLY DRIER WILL IMPACT THE WEST. CANT RULE OUT
SOME STRONG DOWNDRAFTS. AS THE OVERNIGHT PROGRESSES ADDITIONAL JUICE
WILL FUEL WETTER SHOWERS/STORMS. MODELS CONTINUE TO PROJECT THE BEST
RESULTS ACROSS THE NORTHWEST THIRD WITH ANOTHER DEVELOPING AREA
ACROSS THE SOUTH LATE TONIGHT. GUSTY SOUTHERLY WINDS WILL BE FOUND
THROUGH THE REST OF THE AFTERNOON.
THE SOUTHERN AREA OF PRECIPITATION MENTIONED ABOVE SHOULD OVERSPREAD MOST
OF THE AREA DURING THE DAY ON SATURDAY. AREAS ALONG AND SOUTH OF
INTERSTATE 40 STAND TO BENEFIT THE MOST IN TERMS OF SOME WETTING
MOISTURE OR GREATER THAN TENTH OF AN INCH. SOUTHEAST AREAS WILL BE
FAIRLY JUICY MOST OF THE DAY. NEEDLESS TO SAY...HUMIDITY VALUES WILL
BE UNSEASONABLY HIGH ON SATURDAY. STORM MOTION DOEST APPEAR TO BE
ALL THAT FAST ALTHOUGH THE SOUTHERN TIER ACTIVITY WILL BE MOVING
TOWARDS THE NORTHEAST/EAST QUICKER THAN THE NORTHERN ACTIVITY.
THE SOUTHERN CALIFORNIA WAVE WILL PASS OVER THE STATE SATURDAY NIGHT
WITH SOME DRYING FOUND ON THE BACKSIDE INTO SUNDAY. INSTABILITY
SHOWERS WILL BE THE NAME OF THE GAME ACROSS THE WEST AND NORTH AND
PERHAPS SOME COLD FRONTAL SHOWERS AND RESIDUAL WAVE INDUCED LIFT
ACROSS THE NORTHEAST. THE BEST CHANCE OF WETTING MOISTURE ON SUNDAY
WOULD BE FOUND ACROSS THE EAST...SPECIFICALLY NORTHEAST.
MODELS REMAIN CONSISTENT FOR SOME RIDGING OVER THE ROCKIES ON
MONDAY. DRIER AIR WOULD BEGIN TO MOVE IN FROM THE WEST BUT IT
APPEARS TO BE A SLOW PROCESS. PERHAPS SOME DRIER SPOT SHOWERS OVER
THE MOUNTAINS...FAVORING THE CENTRAL MTNS. THE WIND FLOW ASSOCIATED
WITH THE RIDGE LOOKS TO BE LIGHT.
ALL EYES REMAIN ON THE TUESDAY THROUGH THURSDAY PERIOD. AS MENTIONED
ABOVE...MODELS A LITTLE SLOWER WITH THE TROUGH PROGRESSION BUT A
SIMILAR IDEA STANDS. INCREASES IN SOUTH/SOUTHWEST WIND ON TUESDAY.
MIDDLE PORTIONS OF THE ATMOSPHERE STILL LOOK TO BE THE MOST UNSTABLE
TUESDAY...THEN SHIFTS EASTWARD ON WEDNESDAY AS A TRADITIONAL OR
PACIFIC COLD FRONT MOVES OVER THE STATE. THE WINDS APPEAR TO BE
QUITE STRONG ON WEDNESDAY WITH MORE HERKY JERKY OR WIDE GUST SPREAD LIKE
WINDS ON TUESDAY. POST COLD FRONTAL STRONG WINDS WOULD REMAIN ACROSS
A GOOD CHUNK OF THE AREA ON THURSDAY. HAINES AND NEGATIVE
TEMPERATURE ANOMALIES MIGHT BE A LIMITER IN TERMS OF CRITICAL
CONDITIONS THURSDAY. IN THE COMING DAYS...CAN SEE A WATCH BEING
ISSUED FOR THE WEST FOR TUESDAY AN AREAWIDE WATCH FOR WEDNESDAY.
CONFIDENCE IS HIGH FOR THIS MULTI DAY EVENT ALTHOUGH
HAINES/TEMPERATURE ANOMALIES WILL MOST LIKELY FLUCTUATE SOME DUE TO
SPEED AND DEPTH OF THE TROUGH PASSAGE. ANOTHER CAVEAT IN TERMS OF
TUESDAY AND CRITICAL CONDITIONS WOULD BE THICKER HIGH CLOUDS
PRECEDING THE MID AND UPPER LEVEL FRONT.
50
&&
.ABQ WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
506 AM EDT SAT APR 19 2014
.SYNOPSIS...
BROAD HIGH PRESSURE WILL SHIFT FROM ONTARIO AND QUEBEC
TODAY...INTO NEW ENGLAND SUNDAY. THE INFLUENCE OF THIS HIGH
PRESSURE SYSTEM WILL KEEP OUR WEATHER DRY THIS WEEKEND AND INTO
MONDAY. NEAR TO SLIGHTLY BELOW NORMAL TEMPERATURES TODAY...WILL
MODERATE SUNDAY INTO THE UPPER 50S TO MID 60S...AND EVEN MORE SO
MONDAY WITH HIGHS IN UPPER 60S TO LOW 70S. OUR NEXT GOOD CHANCE OF
RAIN WILL COME TUESDAY AS A SHOWERY COLD FRONT PASSES.
&&
.NEAR TERM /THROUGH SUNDAY/...
AFTER SUNRISE...STRGR COLD AIR ADVECTION ABV THE SFC LAYER LEADS
TO COLD ENUF TEMPERATURES AS PER MODEL SOUNDINGS TO SUPPORT SCT-
BKN SC/CU FORMING WITH INSOLATION AND THE DIURNAL GROWTH OF THE
BNDRY LAYER FOR MID TO LATE MORNING. THIS WILL BE ESPECIALLY TRUE
FOR THE UPSLOPE REGIONS OF C NY AND NRN PA. MESOSCALE MODELS ALL
SHOW A BAND OF VERY HIGH RH AT 925 MB ADVECTING SOUTHWARD REACHING
C NY/NRN PA ARND 12Z. AFTER 15Z THE MODELS MIX OUT THIS MOISTURE.
THE EURO/GFS...OUR LOCAL 4KM WRF...WRFARW AND HRRR EVEN GO AS FAR
AS SPITTING OUT A LITTLE LIGHT PRECIP SUGGESTING SOME SPRINKLES.
FOR NOW I JUST INCREASED THE CLD CVR FOR MID TO LATE MORNING AND
THEN MIX IT OUT BY AFTERNOON. WILL REASSESS WHETHER SOME SPRINKLES
WILL BE WARRANTED FOR LATER THIS MORNING WITH NEXT UPDATE. ITS
PRETTY INSIGNIFICANT AND OPTED TO KEEP CURRENT FORECAST GOING
WHICH IS WELL COLLOBARATED WITH NEIGHBORING WFO/S.
FOR SATURDAY NIGHT THROUGH SUNDAY...A LARGE AREA OF SFC HIGH OVER
THE CWA SAT NGT EXTENDING NORTH TO QUEBEC. COLDEST NIGHT COMING UP
WITH LOWS MOSTLY 25 TO 32. SOME RETURN FLOW AS THE HIGH MOVES EAST
SUNDAY BUT SFC WINDS LIGHT. HIGHS STILL IN THE L60S.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/...
350 AM UPDATE...
MODEL CONSENSUS CONTINUES TO ADVERTISE A LARGER SEPARATION BETWEEN
DEPARTING HIGH PRESSURE OFFSHORE NOVA SCOTIA AND LOW PRESSURE
APPROACHING FROM THE WESTERN GREAT LAKES REGION SUNDAY NIGHT-
MONDAY. THIS WILL MEAN BETTER RADIATIONAL COOLING SUNDAY NIGHT
/ESPECIALLY FIRST HALF BEFORE SOME HIGH CLOUDS START TO MOVE
IN/...FOLLOWED BY A PERIOD OF RETURN FLOW AND WARM AIR ADVECTION
MONDAY-MONDAY NIGHT. HAVE FOLLOWED WARMER TREND OF GUIDANCE WITH
HIGHS UPPER 60S TO LOW 70S MONDAY...AFTER 30S TO NEAR 40 FOR LOWS
SUNDAY NIGHT.
LATEST OPERATIONAL RUNS OF GFS/ECMWF/GEM AGREE NOW ON WAITING
UNTIL AFTER 12Z TO SWEEP COLD FRONTAL SHOWERS THROUGH THE REGION.
THE RAIN ITSELF IS A SOLID BET...IT IS JUST A MATTER OF WHICH TIME
OF DAY WILL BE THE MAIN RAINFALL. WENT AHEAD WITH HIGH LIKELIHOOD
OF SHOWERS TUESDAY...AND AS THE TIME NEARS WE WILL BE ABLE TO
BETTER HEM IN WHICH SPECIFIC HOURS WILL BE INVOLVED. FRONT WILL BE
PROGRESSIVE AND MOISTURE INFLUX WILL BE LIMITED ENOUGH...TO WHICH
WE ANTICIPATE LESS THAN A HALF INCH OF RAINFALL OUT OF THIS
SYSTEM. THUS NOT EXPECTING MUCH IMPACT OTHER THAN DAMPENING PLANS
FOR GENERAL OUTDOOR ACTIVITIES. THERMAL PROFILES ALSO TOO STABLE
TO SUPPORT CONVECTION...SO NO LIGHTNING EXPECTED.
RAINFALL DEVELOPMENT AND THEN EVENTUAL COLD AIR ADVECTION TUESDAY WILL
HOLD TEMPERATURES BACK TO UPPER 50S-MID 60S FOR HIGHS...FOLLOWED
BY UPPER 30S-LOW 40S FOR LOWS TUESDAY NIGHT WITH DECREASING CHANCES
FOR SHOWERS.
&&
.LONG TERM /WEDNESDAY THROUGH FRIDAY/...
350 AM UPDATE...
BEHIND SURFACE FRONT FROM TUESDAY...STRONG UPPER TROUGH DIGS INTO
WESTERN GREAT LAKES TUESDAY NIGHT...THEN DROPS ACROSS OUR REGION
WEDNESDAY WITH STRONG COLD AIR ADVECTION. GFS-ECMWF RUNS BOTH KEEP
IT AS AN OPEN WAVE AS IT SWINGS THROUGH...BEFORE DIFFERING ON ITS
EVOLUTION WELL OFFSHORE. 1000-500MB THICKNESSES GET SUB-540
DECAMETERS FOR A TIME...CONTRIBUTING TO THE COLDEST DAY OF THE
PERIOD WITH HIGHS WEDNESDAY IN THE MID 40S TO LOW 50S. STILL A
CHANCE OF SHOWERS AS WELL WITH THAT UPPER WAVE PASSING THROUGH.
DRY LATE WEDNESDAY THROUGH THURSDAY NIGHT WITH HIGH PRESSURE IN
CHARGE AT SURFACE...AND RIDGING OCCURRING ALOFT. TEMPERATURES ALSO
MODERATING...ESPECIALLY BY FRIDAY...BUT NEXT WAVE MAY ALSO BE
APPROACHING BY THEN WITH AN INCREASING CHANCE OF SHOWERS FRIDAY-
FRIDAY NIGHT. TIMING OF COURSE WILL BE SORTED OUT BETTER IN COMING
DAYS.
&&
.AVIATION /08Z SATURDAY THROUGH WEDNESDAY/...
COLD FRONT IS MOVING ACROSS CENTRAL NEW YORK AT THIS TIME AND
EXTENDED FROM ABOUT ONEONTA NY TO TOWANDA PA IN THE WFO BGM
FORECAST AREA. THERE WAS POST FRONTAL BKN-OVC CLOUDS AND JUST A
FEW LINGERING SPRINKLES MAINLY ACROSS OTSEGO CO. THESE INSIGNIFICANT
SPRINKLES/LIGHT SHRA WILL NOT AFFECT ANY TAF SITE ERLY THIS
MORNING.
THE BKN-OVC POST FRONTL CLOUDS WAS MAINLY VFR WITH AREAS OF
MVFR...ESPECIALLY AT KSYR...KRME...KITH AND KBGM. AS THE FRONT
WORKS FARTHER SOUTH LL DRYING WILL OCCUR AND SHUD SCATTER OUT THIS
MOISTURE SO EXPECT JUST SCT CLDS BY ARND 8-10Z.
AFTER SUNRISE...COLDER AIR WILL BLOW IN ABV THE SFC LAYER WHICH
WILL BE DECOUPLED AND HENCE THE SFC DRYING WILL WEAKEN. THIS WILL
LEAD TO A SCT-BKN CU/SC LAYER TO DEVELOP WITH INSOLATION FROM MID
TO LATE MORNING. I EXPECT MAINLY VFR 3500 TO 5000 FEET CLD BASES.
AS THIS OCCURS...STRGR WINDS ALOFT WILL BEGIN TO MIX DOWN TO THE
SFC AND THIS CLOUD LAYER SHUD MIX OUT TO MAINLY CLR SKIES FOR THE
AFTERNOON. CLR SKIES WILL REMAIN AFTER SUNSET.
WINDS WILL SWITCH FROM SW TO NW AFTER FROPA AT KAVP AROUND 07Z OR
SO. REST OF TAF SITES WILL HAVE W-NW WINDS MAINLY 5 TO 10 KNOTS
PRIOR TO SUNRISE. AFTER SUNRISE A DECENT LOW-LEVEL PRESSURE
GRADIENT WILL KICK WINDS UP TO 10 TO 15 KNOTS WITH FREQUENT GUSTS
TO 20 TO 25 KNOTS AS THE WINDS VEER FROM THE NW TO THE N BY AFTERNOON.
WINDS WILL RAPIDLY SUBSIDE AFTER SUNSET.
OUTLOOK...
SUN...VFR.
SUN NGT TO MON...VFR WITH LOCAL MVFR/IFR IF FOG DEVELOPS.
TUE-WED...SHOWERS WITH MVFR POSSIBLE.
&&
.FIRE WEATHER...
2 AM SAT UPDATE...
FOR TODAY MINIMUM RELATIVE HUMIDITIES ARE EXPECTED TO DROP TO THE
30S PERCENT IN FINGER LAKES REGION OF NEW YORK THIS AFTERNOON.
RELATIVE HUMIDITIES WILL DROP TO THE UPPER 20S TO LOWER 30S PERCENT
IN THE REST OF CENTRAL NEW YORK AND NORTHEAST PENNSYLVANIA THIS
AFTERNOON. WINDS WILL BE FROM THE NORTHWEST 10 TO 15 MPH WITH SOME
GUSTS TO 20 MPH AT TIMES. FINE FUELS WERE RUNNING BELOW 10
PERCENT. THIS COMES CLOSE TO OUR RED FLAG CRITERIA IN PA. IN NY
THE CRITERIA IS FOR WIND GUSTS OF 25 MPH OR MORE. BIGGEST QUESTION
WILL BE THE WIND GUSTS IN NE PA AND THAT IS WHERE THE UNCERTAINTY LIES
AT THIS TIME. AFTER COLLABORATION WITH CTP AND PHI WILL ISSUE AN
SPS TO COVER AND DAY SHIFT CAN COORDINATE WITH PA STATE PARTNERS
TO SEE IF RED FLAG IS WARRANTED LATER THIS MORNING.
FUELS WILL BE DRY ENOUGH ON SUNDAY AND MONDAY BUT WINDS WILL BE
UNDER 20 MPH ESPECIALLY SUNDAY WITH THE DEPARTING HIGH. AFTN MIN
RH WILL BE IN THE 20S SUNDAY AND 30S MONDAY.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DJN
NEAR TERM...DJN
SHORT TERM...MDP
LONG TERM...MDP
AVIATION...DJN
FIRE WEATHER...DJN
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
359 AM EDT SAT APR 19 2014
.SYNOPSIS...
BROAD HIGH PRESSURE WILL SHIFT FROM ONTARIO AND QUEBEC
TODAY...INTO NEW ENGLAND SUNDAY. THE INFLUENCE OF THIS HIGH
PRESSURE SYSTEM WILL KEEP OUR WEATHER DRY THIS WEEKEND AND INTO
MONDAY. NEAR TO SLIGHTLY BELOW NORMAL TEMPERATURES TODAY...WILL
MODERATE SUNDAY INTO THE UPPER 50S TO MID 60S...AND EVEN MORE SO
MONDAY WITH HIGHS IN UPPER 60S TO LOW 70S. OUR NEXT GOOD CHANCE OF
RAIN WILL COME TUESDAY AS A SHOWERY COLD FRONT PASSES.
&&
.NEAR TERM /THROUGH SUNDAY/...
RADAR SHOWS WEAKENING SPRINKLES ACRS OTSEGO CO AS WK SFC FRNT
SLOWLY SLIPS S AND E ACRS C NY AND NE PA. FRNT EXTENDED ROUGHLY
FROM ONEONTA NY TO ABT TOWANDA PA. THIS FRNT WAS TIED TO AN UPR
LVL WAVE THAT WAS MOVG ACRS NRN NEW ENGLAND AND HENCE DEEPEST LIFT
WAS FARTHER EAST WHERE THERE WAS MORE FRONTAL PRECIPITATION. BY
12Z...FRNT WILL BE S INTO SRN PA WHERE IT WASHES OUT. INITIALLY
THERE WILL BE A BATCH OF BKN POST FRONTAL CLDS THAT WILL ADVECT
SOUTHWARD INTO NRN PA BY 9Z AND THEN DISSIPATE. SO HAVE VARYING
AMNTS OF CLD CVR FOR THE REMAINING OVERNIGHT HOURS.
AFTER SUNRISE...STRGR COLD AIR ADVECTION ABV THE SFC LAYER LEADS
TO COLD ENUF TEMPERATURES AS PER MODEL SOUNDINGS TO SUPPORT SCT-
BKN SC/CU FORMING WITH INSOLATION AND THE DIURNAL GROWTH OF THE
BNDRY LAYER FOR MID TO LATE MORNING. THIS WILL BE ESPECIALLY TRUE
FOR THE UPSLOPE REGIONS OF C NY AND NRN PA. MESOSCALE MODELS ALL
SHOW A BAND OF VERY HIGH RH AT 925 MB ADVECTING SOUTHWARD
REACHING C NY/NRN PA ARND 12Z. AFTER 15Z THE MODELS MIX OUT THIS
MOISTURE. THE EURO/GFS...OUR LOCAL 4KM WRF...WRFARW AND HRRR EVEN
GO AS FAR AS SPITTING OUT A LITTLE LIGHT PRECIP SUGGESTING SOME
SPRINKLES. FOR NOW I JUST INCREASED THE CLD CVR FOR MID TO LATE
MORNING AND THEN MIX IT OUT BY AFTERNOON. WILL REASSESS WHETHER
SOME SPRINKLES WILL BE WARRANTED FOR LATER THIS MORNING WITH NEXT
UPDATE. ITS PRETTY INSIGNIFICANT AND OPTED TO KEEP CURRENT
FORECAST GOING WHICH IS WELL COLLOBARATED WITH NEIGHBORING WFO/S.
FOR SATURDAY NIGHT THROUGH SUNDAY...A LARGE AREA OF SFC HIGH OVER
THE CWA SAT NGT EXTENDING NORTH TO QUEBEC. COLDEST NIGHT COMING UP
WITH LOWS MOSTLY 25 TO 32. SOME RETURN FLOW AS THE HIGH MOVES EAST
SUNDAY BUT SFC WINDS LIGHT. HIGHS STILL IN THE L60S.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/...
350 AM UPDATE...
MODEL CONSENSUS CONTINUES TO ADVERTISE A LARGER SEPARATION BETWEEN
DEPARTING HIGH PRESSURE OFFSHORE NOVA SCOTIA AND LOW PRESSURE
APPROACHING FROM THE WESTERN GREAT LAKES REGION SUNDAY NIGHT-
MONDAY. THIS WILL MEAN BETTER RADIATIONAL COOLING SUNDAY NIGHT
/ESPECIALLY FIRST HALF BEFORE SOME HIGH CLOUDS START TO MOVE
IN/...FOLLOWED BY A PERIOD OF RETURN FLOW AND WARM AIR ADVECTION
MONDAY-MONDAY NIGHT. HAVE FOLLOWED WARMER TREND OF GUIDANCE WITH
HIGHS UPPER 60S TO LOW 70S MONDAY...AFTER 30S TO NEAR 40 FOR LOWS
SUNDAY NIGHT.
LATEST OPERATIONAL RUNS OF GFS/ECMWF/GEM AGREE NOW ON WAITING
UNTIL AFTER 12Z TO SWEEP COLD FRONTAL SHOWERS THROUGH THE REGION.
THE RAIN ITSELF IS A SOLID BET...IT IS JUST A MATTER OF WHICH TIME
OF DAY WILL BE THE MAIN RAINFALL. WENT AHEAD WITH HIGH LIKELIHOOD
OF SHOWERS TUESDAY...AND AS THE TIME NEARS WE WILL BE ABLE TO
BETTER HEM IN WHICH SPECIFIC HOURS WILL BE INVOLVED. FRONT WILL BE
PROGRESSIVE AND MOISTURE INFLUX WILL BE LIMITED ENOUGH...TO WHICH
WE ANTICIPATE LESS THAN A HALF INCH OF RAINFALL OUT OF THIS
SYSTEM. THUS NOT EXPECTING MUCH IMPACT OTHER THAN DAMPENING PLANS
FOR GENERAL OUTDOOR ACTIVITIES. THERMAL PROFILES ALSO TOO STABLE
TO SUPPORT CONVECTION...SO NO LIGHTNING EXPECTED.
RAINFALL DEVELOPMENT AND THEN EVENTUAL COLD AIR ADVECTION TUESDAY WILL
HOLD TEMPERATURES BACK TO UPPER 50S-MID 60S FOR HIGHS...FOLLOWED
BY UPPER 30S-LOW 40S FOR LOWS TUESDAY NIGHT WITH DECREASING CHANCES
FOR SHOWERS.
&&
.LONG TERM /WEDNESDAY THROUGH FRIDAY/...
350 AM UPDATE...
BEHIND SURFACE FRONT FROM TUESDAY...STRONG UPPER TROUGH DIGS INTO
WESTERN GREAT LAKES TUESDAY NIGHT...THEN DROPS ACROSS OUR REGION
WEDNESDAY WITH STRONG COLD AIR ADVECTION. GFS-ECMWF RUNS BOTH KEEP
IT AS AN OPEN WAVE AS IT SWINGS THROUGH...BEFORE DIFFERING ON ITS
EVOLUTION WELL OFFSHORE. 1000-500MB THICKNESSES GET SUB-540
DECAMETERS FOR A TIME...CONTRIBUTING TO THE COLDEST DAY OF THE
PERIOD WITH HIGHS WEDNESDAY IN THE MID 40S TO LOW 50S. STILL A
CHANCE OF SHOWERS AS WELL WITH THAT UPPER WAVE PASSING THROUGH.
DRY LATE WEDNESDAY THROUGH THURSDAY NIGHT WITH HIGH PRESSURE IN
CHARGE AT SURFACE...AND RIDGING OCCURRING ALOFT. TEMPERATURES ALSO
MODERATING...ESPECIALLY BY FRIDAY...BUT NEXT WAVE MAY ALSO BE
APPROACHING BY THEN WITH AN INCREASING CHANCE OF SHOWERS FRIDAY-
FRIDAY NIGHT. TIMING OF COURSE WILL BE SORTED OUT BETTER IN COMING
DAYS.
&&
.AVIATION /08Z SATURDAY THROUGH WEDNESDAY/...
COLD FRONT IS MOVING ACROSS CENTRAL NEW YORK AT THIS TIME AND
EXTENDED FROM ABOUT ONEONTA NY TO TOWANDA PA IN THE WFO BGM
FORECAST AREA. THERE WAS POST FRONTAL BKN-OVC CLOUDS AND JUST A
FEW LINGERING SPRINKLES MAINLY ACROSS OTSEGO CO. THESE INSIGNIFICANT
SPRINKLES/LIGHT SHRA WILL NOT AFFECT ANY TAF SITE ERLY THIS
MORNING.
THE BKN-OVC POST FRONTL CLOUDS WAS MAINLY VFR WITH AREAS OF
MVFR...ESPECIALLY AT KSYR...KRME...KITH AND KBGM. AS THE FRONT
WORKS FARTHER SOUTH LL DRYING WILL OCCUR AND SHUD SCATTER OUT THIS
MOISTURE SO EXPECT JUST SCT CLDS BY ARND 8-10Z.
AFTER SUNRISE...COLDER AIR WILL BLOW IN ABV THE SFC LAYER WHICH
WILL BE DECOUPLED AND HENCE THE SFC DRYING WILL WEAKEN. THIS WILL
LEAD TO A SCT-BKN CU/SC LAYER TO DEVELOP WITH INSOLATION FROM MID
TO LATE MORNING. I EXPECT MAINLY VFR 3500 TO 5000 FEET CLD BASES.
AS THIS OCCURS...STRGR WINDS ALOFT WILL BEGIN TO MIX DOWN TO THE
SFC AND THIS CLOUD LAYER SHUD MIX OUT TO MAINLY CLR SKIES FOR THE
AFTERNOON. CLR SKIES WILL REMAIN AFTER SUNSET.
WINDS WILL SWITCH FROM SW TO NW AFTER FROPA AT KAVP AROUND 07Z OR
SO. REST OF TAF SITES WILL HAVE W-NW WINDS MAINLY 5 TO 10 KNOTS
PRIOR TO SUNRISE. AFTER SUNRISE A DECENT LOW-LEVEL PRESSURE
GRADIENT WILL KICK WINDS UP TO 10 TO 15 KNOTS WITH FREQUENT GUSTS
TO 20 TO 25 KNOTS AS THE WINDS VEER FROM THE NW TO THE N BY AFTERNOON.
WINDS WILL RAPIDLY SUBSIDE AFTER SUNSET.
OUTLOOK...
SUN...VFR.
SUN NGT TO MON...VFR WITH LOCAL MVFR/IFR IF FOG DEVELOPS.
TUE-WED...SHOWERS WITH MVFR POSSIBLE.
&&
.FIRE WEATHER...
2 PM FRI UPDATE...
NO FIRE WEATHER CONCERNS THROUGH MONDAY. VERY LITTLE RAINFALL THIS
EVENING WITH LESS THAN A TENTH OF AN INCH IN NY. NONE IN NE PA.
NEXT CHANCE OF RAIN MONDAY NIGHT AND TUESDAY.
THIS AFTERNOON...RH FALLING INTO THE 30S BUT WINDS ONLY 5 TO 15
MPH. SATURDAY INCREASING WINDS AND SUNSHINE. ERN AREAS COULD HAVE
GUSTS OVER 20 MPH. RH FALLING TO 25 TO 40 PERCENT. WILL HAVE TO
WATCH THIS AND SEE IF THE 10 HOUR FUELS DRY ENOUGH.
FUELS WILL BE DRY ENOUGH ON SUNDAY AND MONDAY BUT WINDS WILL BE
UNDER 20 MPH ESPECIALLY SUNDAY WITH THE DEPARTING HIGH. AFTN MIN
RH WILL BE IN THE 20S SUNDAY AND 30S MONDAY.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...DJN/MDP
NEAR TERM...DJN/TAC
SHORT TERM...MDP
LONG TERM...MDP
AVIATION...DJN
FIRE WEATHER...
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
221 AM EDT SAT APR 19 2014
.SYNOPSIS...
A WEAK COLD FRONT WILL BRING A FEW LIGHT SHOWERS OR SPRINKLES
TONIGHT TO CENTRAL NEW YORK. DRY WEATHER WILL THEN RETURN
SATURDAY, LASTING INTO MONDAY. AFTER A SLIGHT COOL DOWN ON
SATURDAY, TEMPERATURES WILL MODERATE SUNDAY AND MONDAY INTO THE
60S.
&&
.NEAR TERM /THROUGH TODAY/...
RADAR SHOWS WEAKENING SPRINKLES ACRS OTSEGO CO AS WK SFC FRNT
SLOWLY SLIPS S AND E ACRS C NY AND NE PA. FRNT EXTENDED ROUGHLY
FROM ONEONTA NY TO ABT TOWANDA PA. THIS FRNT WAS TIED TO AN UPR
LVL WAVE THAT WAS MOVG ACRS NRN NEW ENGLAND AND HENCE DEEPEST LIFT
WAS FARTHER EAST WHERE THERE WAS MORE FRONTAL PRECIPITATION. BY
12Z...FRNT WILL BE S INTO SRN PA WHERE IT WASHES OUT. INITIALLY
THERE WILL BE A BATCH OF BKN POST FRONTAL CLDS THAT WILL ADVECT
SOUTHWARD INTO NRN PA BY 9Z AND THEN DISSIPATE. SO HAVE VARYING
AMNTS OF CLD CVR FOR THE REMAINING OVERNIGHT HOURS.
AFTER SUNRISE...STRGR COLD AIR ADVECTION ABV THE SFC LAYER LEADS
TO COLD ENUF TEMPERATURES AS PER MODEL SOUNDINGS TO SUPPORT SCT-
BKN SC/CU FORMING WITH INSOLATION AND THE DIURNAL GROWTH OF THE
BNDRY LAYER FOR MID TO LATE MORNING. THIS WILL BE ESPECIALLY TRUE
FOR THE UPSLOPE REGIONS OF C NY AND NRN PA. MESOSCALE MODELS ALL
SHOW A BAND OF VERY HIGH RH AT 925 MB ADVECTING SOUTHWARD
REACHING C NY/NRN PA ARND 12Z. AFTER 15Z THE MODELS MIX OUT THIS
MOISTURE. THE EURO/GFS...OUR LOCAL 4KM WRF...WRFARW AND HRRR EVEN
GO AS FAR AS SPITTING OUT A LITTLE LIGHT PRECIP SUGGESTING SOME
SPRINKLES. FOR NOW I JUST INCREASED THE CLD CVR FOR MID TO LATE
MORNING AND THEN MIX IT OUT BY AFTERNOON. WILL REASSESS WHETHER
SOME SPRINKLES WILL BE WARRANTED FOR LATER THIS MORNING WITH NEXT
UPDATE. ITS PRETTY INSIGNIFICANT AND OPTED TO KEEP CURRENT
FORECAST GOING WHICH IS WELL COLLOBARATED WITH NEIGHBORING WFO/S.
&&
.SHORT TERM /TONIGHT THROUGH MONDAY/...
2 PM UPDATE...
A LARGE AREA OF SFC HIGH OVER THE CWA SAT NGT EXTENDING NORTH TO
QUEBEC. COLDEST NIGHT COMING UP WITH LOWS MOSTLY 25 TO 32. SOME
RETURN FLOW AS THE HIGH MOVES EAST SUNDAY BUT SFC WINDS LIGHT.
HIGHS STILL IN THE L60S.
INITIAL SFC LOW TRACKS WELL NORTH OF THE CWA LAYING DOWN A FRONT
IN SE CANADA. PRECIP WILL BE STAY IN CANADA WITH A UPPER LEVEL
ZONAL FLOW.
FOR RAIN WILL HAVE TO WAIT UNTIL AT LEAST MONDAY NIGHT AS A SHORT
WAVE DIGS A TROF INTO THE UPPER LAKES. LOWERED POPS TO NOTHING
SUNDAY NIGHT AND MONDAY MORNING. ONLY SCHC POPS FAR NW MON AFTN.
MODELS CONTINUE TO SLOW PROGRESS OF COLD FRONT.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
130 PM UPDATE...
MED RANGE MODELS ARE SHOWING DRY FOR MON NGT AND HV PULLED POPS
DOWN TO SLGT CHC CWA-WIDE WITH LKLY POPS FOR TUE AS FNT COMES
THRU. LINGERING PCPN EXPECTED TUE NGT AS UL TROF SWINGS THRU. 12Z
GFS INDICATES H5 LOW DVLPNG OVR THE COAST WHILE 00Z EURO KEEPS IT
AS AN OPEN WV. FOR THE TIME BEING HV GONE WITH CHC SHOWERS ON WED
FOR ERN SXNS.
1020MB HIGH PRESSURE BUILDS IN FM THE WEST ON THUR LEADING TO DRY
WX THRU THE END OF THE EXTNDD. HIGH TEMPS FOLLOWING FROPA ON WED
WL DROP TO BLO SEASONAL NORMS FOR A DAY AND THEN REBOUND UNDER
S/WV RIDGING.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
COLD FRONT IS MOVING ACROSS CENTRAL NEW YORK AT THIS TIME AND
EXTENDED FROM ABOUT ONEONTA NY TO TOWANDA PA IN THE WFO BGM
FORECAST AREA. THERE WAS POST FRONTAL BKN-OVC CLOUDS AND JUST A
FEW LINGERING SPRINKLES MAINLY ACROSS OTSEGO CO. THESE INSIGNIFICANT
SPRINKLES/LIGHT SHRA WILL NOT AFFECT ANY TAF SITE ERLY THIS
MORNING.
THE BKN-OVC POST FRONTL CLOUDS WAS MAINLY VFR WITH AREAS OF
MVFR...ESPECIALLY AT KSYR...KRME...KITH AND KBGM. AS THE FRONT
WORKS FARTHER SOUTH LL DRYING WILL OCCUR AND SHUD SCATTER OUT THIS
MOISTURE SO EXPECT JUST SCT CLDS BY ARND 8-10Z.
AFTER SUNRISE...COLDER AIR WILL BLOW IN ABV THE SFC LAYER WHICH
WILL BE DECOUPLED AND HENCE THE SFC DRYING WILL WEAKEN. THIS WILL
LEAD TO A SCT-BKN CU/SC LAYER TO DEVELOP WITH INSOLATION FROM MID
TO LATE MORNING. I EXPECT MAINLY VFR 3500 TO 5000 FEET CLD BASES.
AS THIS OCCURS...STRGR WINDS ALOFT WILL BEGIN TO MIX DOWN TO THE
SFC AND THIS CLOUD LAYER SHUD MIX OUT TO MAINLY CLR SKIES FOR THE
AFTERNOON. CLR SKIES WILL REMAIN AFTER SUNSET.
WINDS WILL SWITCH FROM SW TO NW AFTER FROPA AT KAVP AROUND 07Z OR
SO. REST OF TAF SITES WILL HAVE W-NW WINDS MAINLY 5 TO 10 KNOTS
PRIOR TO SUNRISE. AFTER SUNRISE A DECENT LOW-LEVEL PRESSURE
GRADIENT WILL KICK WINDS UP TO 10 TO 15 KNOTS WITH FREQUENT GUSTS
TO 20 TO 25 KNOTS AS THE WINDS VEER FROM THE NW TO THE N BY AFTERNOON.
WINDS WILL RAPIDLY SUBSIDE AFTER SUNSET.
OUTLOOK...
SUN...VFR.
SUN NGT TO MON...VFR WITH LOCAL MVFR/IFR IF FOG DEVELOPS.
TUE-WED...SHOWERS WITH MVFR POSSIBLE.
&&
.FIRE WEATHER...
2 PM FRI UPDATE...
NO FIRE WEATHER CONCERNS THROUGH MONDAY. VERY LITTLE RAINFALL THIS
EVENING WITH LESS THAN A TENTH OF AN INCH IN NY. NONE IN NE PA.
NEXT CHANCE OF RAIN MONDAY NIGHT AND TUESDAY.
THIS AFTERNOON...RH FALLING INTO THE 30S BUT WINDS ONLY 5 TO 15
MPH. SATURDAY INCREASING WINDS AND SUNSHINE. ERN AREAS COULD HAVE
GUSTS OVER 20 MPH. RH FALLING TO 25 TO 40 PERCENT. WILL HAVE TO
WATCH THIS AND SEE IF THE 10 HOUR FUELS DRY ENOUGH.
FUELS WILL BE DRY ENOUGH ON SUNDAY AND MONDAY BUT WINDS WILL BE
UNDER 20 MPH ESPECIALLY SUNDAY WITH THE DEPARTING HIGH. AFTN MIN
RH WILL BE IN THE 20S SUNDAY AND 30S MONDAY.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...TAC
NEAR TERM...DJN
SHORT TERM...TAC
LONG TERM...PVN
AVIATION...DJN
FIRE WEATHER...
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
943 PM EDT SUN APR 20 2014
.SYNOPSIS...
LOW PRESSURE OFF OF CAPE FEAR WILL DRIFT SLOWLY EAST NORTHEAST
AND FARTHER OFFSHORE THROUGH MONDAY. WEAK HIGH PRESSURE WILL
CROSS THE AREA MONDAY NIGHT. A COLD FRONT WILL APPROACH FROM THE
WEST TUESDAY AND CROSS THE REGION TUESDAY NIGHT. HIGH PRESSURE
WILL BUILD IN BEHIND THE FRONT WEDNESDAY AND THURSDAY THEN MOVE
OFF THE COAST FRIDAY. A WEAK COLD FRONT WILL MOVE INTO THE AREA
SATURDAY.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
AS OF 940 PM SUNDAY...BASED ON CURRENT RADAR COVERAGE...HAVE AGAIN
LOWERED POPS FOR THE OVERNIGHT HOURS WITH JUST LOW CHANCE ALONG
THE COAST WITH THE HEAVIER PRECIPITATION NOW OFFSHORE. POPS WILL
BE MINIMAL WEST OF HIGHWAY 17 OVERNIGHT. THIS TREND IS SUPPORTED
BY LATEST 3 KM HRRR AND RAP MODELS. LOW TEMPERATURES LOOK TO BE IN
GOOD SHAPE SO NO OTHER CHANGES NEEDED.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH 6 PM MONDAY/...
VERY GRADUAL CLEARING EXPECTED ON MONDAY AS THE SLOW MOVING
OFFSHORE LOW PRESSURE FINALLY LOOSENS ITS GRIP ON EASTERN NC. MAY
BE SOME LINGERING RAIN ESP ON THE OUTER BANKS IN THE MORNING BUT
THE TREND SHUD BE FOR DECREASING CLOUDS AND DIMINISHING WIND
INLAND AS LOW CLOUDS SCOUR OUT. SHUD SEE AT LEAST PARTIAL SUNSHINE
DURING THE AFTERNOON OVER INLAND AREAS. HIGHS WILL REMAIN BELOW
SEASONAL AVERAGES THO WITH NEAR 70 READINGS INLAND AND 60S CLOSER
TO THE COAST.
&&
.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
AS OF 330 PM SUN...WEAK RIDGING WILL BE OVER THE AREA MON NIGHT
AHEAD OF A ROBUST MID LEVEL TROUGH PUSHING INTO THE OHIO AND
TENN RIVER VALLEYS. THE ATTENDANT COLD FRONT WILL APPROACH THE
REGION TUES WITH SW LOW LEVEL FLOW INCREASING THROUGH THE DAY.
PRECIP CHANCES INCREASE LATE TUES AFTERNOON AND EVENING AS UPPER
LEVEL DYNAMICS IMPROVE AHEAD OF THE TROUGH. WEAK TO MODEST
INSTABILITY AND DESCENT MID LEVEL LAPSE RATES WILL BE IN PLACE AND
COULD SEE A FEW THUNDERSTORMS DEVELOP. MOISTURE LOOKS SOMEWHAT
LIMITED THOUGH WITH HIGH PRES ACROSS THE GULF OF MEXICO AND QPF
AMOUNTS LOOK LIGHT...GENERALLY LESS THAN A QUARTER INCH. SWLY FLOW
BRINGS A MODEST WARM UP TUES WITH HIGHS EXPECTED AROUND 80 INLAND
TO AROUND 70 ALONG THE COAST. CAA RAMPS UP LATE TUES NIGHT AFTER
THE FRONTAL PASSAGE WITH HIGH PRES BUILDING INTO THE REGION FROM
THE N FOR WED AND THURS. DRY CONDITIONS WILL PREVAIL WITH TEMPS A
LITTLE BELOW NORMAL WITH HIGHS IN THE UPPER 60S/LOWER 70S INLAND
TO MID 60S ALONG THE COAST. THE HIGH MOVES OFFSHORE FRI WITH SW
FLOW AND MOISTURE INCREASING AHEAD OF THE NEXT MID LEVEL SYSTEM
APPROACHING FROM THE WEST. TEMPS CLIMB BACK ABOVE NORMAL WITH
HIGHS EXPECTED AROUND 80 INLAND TO LOW/MID 70S COAST. KEEPING SLT
CHC TO LOW END CHC POPS FRI AFTERNOON/EVENING AS UPPER LEVEL
SUPPORT LOOKS RATHER WEAK. MODELS ARE DEPICTING MODERATE
INSTABILITY AND COULD SEE A FEW THUNDERSTORMS DEVELOP AS WELL.
CYCLONIC FLOW CONTINUES ALOFT NEXT WEEKEND WITH AN UPPER LOW
TRACKING ACROSS NEW ENGLAND. A BACKDOOR COLD FRONT PUSHES SOUTH
ACROSS THE AREA SAT EVENING AND SOME MODELS INDICATING A FEW
SHOWERS POSSIBLE ACROSS SRN SECTIONS...BUT WITH LIMITED CONFIDENCE
KEEPING POPS BELOW 15 PERCENT.
&&
.AVIATION /02Z MONDAY THROUGH FRIDAY/...
SHORT TERM /THROUGH 18Z MONDAY/...
AS OF 655 PM SUNDAY...EXPECT CEILINGS TO CONTINUE TO BOUNCE
BETWEEN MVFR/IFR THROUGH MOST OF THE NIGHT. PRECIPITATION
CONTINUES TO DIMINISH AND SOME CLEARING MAY OCCUR AT KPGV/KISO
LATER TONIGHT...BUT WILL FOLLOW PERSISTENCE FROM THE PREVIOUS
FORECAST.
LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
AS OF 330 PM SUN...LINGERING LOW LEVEL MOISTURE MAY CONTINUE TO
BRING MVFR CIGS TO COASTAL TAF SITES MON NIGHT BUT OTHERWISE VFR
IS EXPECTED TO DOMINATE THROUGH TUES. A PERIOD OF SUB-VFR MAY
OCCUR WITH A FEW SHOWERS LATE TUESDAY AFTERNOON AND EVENING AHEAD
OF THE NEXT COLD FRONT. HIGH PRES BUILD IN WED THROUGH FRI
BRINGING PREDOMINANTLY VFR CONDITIONS ACROSS RTES.
&&
.MARINE...
SHORT TERM /THROUGH MONDAY/...
AS OF 945 PM SUNDAY...NO CHANGES TO CURRENT HEADLINES. WINDS HAVE
SUBSIDED A BIT...BUT DIAMOND BUOY IS STILL GUSTING TO 39 KNOTS.
GALE WARNINGS ALL EXPIRE AT 2 AM AND MAY BE ABLE TO DROP ON THE
NEXT UPDATE...BUT WOULD PREFER TO WAIT AND SEE IF THIS TREND
CONTINUES. SMALL CRAFT ADVISORIES CONTINUE ON ALL OTHER WATERS AND
GUSTY NORTH WINDS CONTINUE. SEAS REMAIN VERY ROUGH AND ARE IN THE
13 TO 16 FOOT RANGE ON THE COASTAL WATERS FROM OCRACOKE NORTH.
WILL LIKELY MAKE TWEAKS TO THE COASTAL FORECAST BASED ON THE NEXT
BATCH OF BUOY OBSERVATIONS.
LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
AS OF 330 PM SUN...NLY WINDS DIMINISH TO LESS THAN 15 KT MON NIGHT
AS LOW PRES PUSHES EAST OF THE AREA AND HIGH PRES WEAKENS. SEAS
AS HIGH AS 6-8 FT NORTH AND 3-7 FT SOUTH EXPECTED TO START MON
NIGHT BUT ARE PROGGED TO DROP TO 5 FT OR LESS TUES MORNING. WINDS
THEN SHIFT TO SW TUES AND INCREASE TO 10-20 KT BY LATE IN THE DAY
AHEAD OF A COLD FRONT APPROACHING FROM THE NW. COULD SEE MINIMAL
SCA CONDITIONS DEVELOP TUES EVENING ACROSS THE CENTRAL WATERS AS
SEAS BUILD UP TO 6 FT IN SW FLOW AHEAD OF THE FRONT. THE FRONT
WILL CROSS THE WATERS TUES NIGHT WITH A NWLY SURGE AROUND 15-25 KT
LATE TUES NIGHT AND WED. SEAS FORECAST TO BUILD TO 4-7 FT NORTH OF
CAPE LOOKOUT LATE TUES NIGHT BRINGING SCA CONDITIONS ACROSS MUCH
OF THE WATERS...HOWEVER MODELS KEEP WINDS AROUND 15-20 KT WITH
SEAS AROUND 3-5 FT SOUTH OF CAPE LOOKOUT. HIGH PRES BUILDS INTO
THE AREA THURS AND FRI WITH SUB SCA CONDITIONS EXPECTED. WINDS DO
INCREASE THROUGH THE DAY FRI AHEAD OF THE NEXT COLD FRONT WITH SW
WINDS INCREASING TO 10-20 KT AND SEAS BUILDING TO 3-5 FT FRI
AFTERNOON AND EVENING.
&&
.TIDES/COASTAL FLOODING...
WAVES IN THE SURF ZONE WILL LIKELY REMAIN 8+ FT ON THE OUTER
BANKS NORTH OF CAPE HATTERAS...SO CONT HIGH SURF ADVRY THRU
TONIGHT INTO MONDAY. BASED ON DATA FROM THE TIDE GAUGE IN
ORIENTAL...WILL CONTINUE COASTAL FLOOD ADVISORY OVERNIGHT. WATER
LEVELS CONTINUE 2 TO 3 FEET ABOVE NORMAL SRN PAMLICO SOUND WITH
PERSISTENT NE FLOW.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...HIGH SURF ADVISORY UNTIL 2 PM EDT MONDAY FOR NCZ103.
COASTAL FLOOD ADVISORY UNTIL 8 AM EDT MONDAY FOR NCZ093>095.
MARINE...SMALL CRAFT ADVISORY UNTIL 2 AM EDT MONDAY FOR AMZ136-137.
GALE WARNING UNTIL 2 AM EDT MONDAY FOR AMZ135-152-154-156-158.
SMALL CRAFT ADVISORY UNTIL 8 AM EDT MONDAY FOR AMZ130-131.
SMALL CRAFT ADVISORY UNTIL 7 AM EDT TUESDAY FOR AMZ150.
&&
$$
SYNOPSIS...BTC
NEAR TERM...CTC
SHORT TERM...BTC
LONG TERM...BTC/SK
AVIATION...CTC/SK/LEP
MARINE...CTC/BTC/SK
TIDES/COASTAL FLOODING...CTC
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
703 PM EDT SUN APR 20 2014
.SYNOPSIS...
LOW PRESSURE OFF OF CAPE FEAR WILL DRIFT SLOWLY EAST NORTHEAST
AND FARTHER OFFSHORE THROUGH MONDAY. WEAK HIGH PRESSURE WILL
CROSS THE AREA MONDAY NIGHT. A COLD FRONT WILL APPROACH FROM THE
WEST TUESDAY AND CROSS THE REGION TUESDAY NIGHT. HIGH PRESSURE
WILL BUILD IN BEHIND THE FRONT WEDNESDAY AND THURSDAY THEN MOVE
OFF THE COAST FRIDAY. A WEAK COLD FRONT WILL MOVE INTO THE AREA
SATURDAY.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
AS OF 655 PM SUNDAY...PRECIPITATION IS SLOWLY DIMINISHING IN
COVERAGE AND INTENSITY. THIS IS WELL DEPICTED BY THE 3 KM HRRR AND
RAP MODELS. BASED ON RADAR TRENDS...WILL KEEP LIKELY POPS NEAR THE
COAST...TAPERING TO CHANCE WELL INLAND. THE HEAVIER PRECIPITATION
LOOKS TO STAY OFFSHORE. GUSTY NORTHEAST TO NORTH WINDS WILL
PERSIST THROUGH THE OVERNIGHT HOURS. MADE TO ADJUSTMENTS TO
CURRENT MINIMUM TEMPERATURE FORECAST AT THIS TIME.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH 6 PM MONDAY/...
VERY GRADUAL CLEARING EXPECTED ON MONDAY AS THE SLOW MOVING
OFFSHORE LOW PRESSURE FINALLY LOOSENS ITS GRIP ON EASTERN NC. MAY
BE SOME LINGERING RAIN ESP ON THE OUTER BANKS IN THE MORNING BUT
THE TREND SHUD BE FOR DECREASING CLOUDS AND DIMINISHING WIND
INLAND AS LOW CLOUDS SCOUR OUT. SHUD SEE AT LEAST PARTIAL SUNSHINE
DURING THE AFTERNOON OVER INLAND AREAS. HIGHS WILL REMAIN BELOW
SEASONAL AVERAGES THO WITH NEAR 70 READINGS INLAND AND 60S CLOSER
TO THE COAST.
&&
.LONG TERM /MONDAY NIGHT THROUGH SUNDAY/...
AS OF 330 PM SUN...WEAK RIDGING WILL BE OVER THE AREA MON NIGHT
AHEAD OF A ROBUST MID LEVEL TROUGH PUSHING INTO THE OHIO AND
TENN RIVER VALLEYS. THE ATTENDANT COLD FRONT WILL APPROACH THE
REGION TUES WITH SW LOW LEVEL FLOW INCREASING THROUGH THE DAY.
PRECIP CHANCES INCREASE LATE TUES AFTERNOON AND EVENING AS UPPER
LEVEL DYNAMICS IMPROVE AHEAD OF THE TROUGH. WEAK TO MODEST
INSTABILITY AND DESCENT MID LEVEL LAPSE RATES WILL BE IN PLACE AND
COULD SEE A FEW THUNDERSTORMS DEVELOP. MOISTURE LOOKS SOMEWHAT
LIMITED THOUGH WITH HIGH PRES ACROSS THE GULF OF MEXICO AND QPF
AMOUNTS LOOK LIGHT...GENERALLY LESS THAN A QUARTER INCH. SWLY FLOW
BRINGS A MODEST WARM UP TUES WITH HIGHS EXPECTED AROUND 80 INLAND
TO AROUND 70 ALONG THE COAST. CAA RAMPS UP LATE TUES NIGHT AFTER
THE FRONTAL PASSAGE WITH HIGH PRES BUILDING INTO THE REGION FROM
THE N FOR WED AND THURS. DRY CONDITIONS WILL PREVAIL WITH TEMPS A
LITTLE BELOW NORMAL WITH HIGHS IN THE UPPER 60S/LOWER 70S INLAND
TO MID 60S ALONG THE COAST. THE HIGH MOVES OFFSHORE FRI WITH SW
FLOW AND MOISTURE INCREASING AHEAD OF THE NEXT MID LEVEL SYSTEM
APPROACHING FROM THE WEST. TEMPS CLIMB BACK ABOVE NORMAL WITH
HIGHS EXPECTED AROUND 80 INLAND TO LOW/MID 70S COAST. KEEPING SLT
CHC TO LOW END CHC POPS FRI AFTERNOON/EVENING AS UPPER LEVEL
SUPPORT LOOKS RATHER WEAK. MODELS ARE DEPICTING MODERATE
INSTABILITY AND COULD SEE A FEW THUNDERSTORMS DEVELOP AS WELL.
CYCLONIC FLOW CONTINUES ALOFT NEXT WEEKEND WITH AN UPPER LOW
TRACKING ACROSS NEW ENGLAND. A BACKDOOR COLD FRONT PUSHES SOUTH
ACROSS THE AREA SAT EVENING AND SOME MODELS INDICATING A FEW
SHOWERS POSSIBLE ACROSS SRN SECTIONS...BUT WITH LIMITED CONFIDENCE
KEEPING POPS BELOW 15 PERCENT.
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
SHORT TERM /THROUGH 18Z MONDAY/...
AS OF 655 PM SUNDAY...EXPECT CEILINGS TO CONTINUE TO BOUNCE
BETWEEN MVFR/IFR THROUGH MOST OF THE NIGHT. PRECIPITATION
CONTINUES TO DIMINISH AND SOME CLEARING MAY OCCUR AT KPGV/KISO
LATER TONIGHT...BUT WILL FOLLOW PERSISTENCE FROM THE PREVIOUS
FORECAST.
LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
AS OF 330 PM SUN...LINGERING LOW LEVEL MOISTURE MAY CONTINUE TO
BRING MVFR CIGS TO COASTAL TAF SITES MON NIGHT BUT OTHERWISE VFR
IS EXPECTED TO DOMINATE THROUGH TUES. A PERIOD OF SUB-VFR MAY
OCCUR WITH A FEW SHOWERS LATE TUESDAY AFTERNOON AND EVENING AHEAD
OF THE NEXT COLD FRONT. HIGH PRES BUILD IN WED THROUGH FRI
BRINGING PREDOMINANTLY VFR CONDITIONS ACROSS RTES.
&&
.MARINE...
SHORT TERM /THROUGH MONDAY/...
CONTINUE ALL HEADLINES AS WINDS CONTINUE TO GUSTS WELL INTO THE
30S IN THE GALE WARNING AREAS AND EVEN CLOSE TO 30 KNOTS IN THE
SMALL CRAFT ADVISORY AREAS. SEAS CONTINUE VERY HIGH WITH UP TO 17
FEET AT DIAMOND BUOY AND THE BUOY 13 MILES EAST OF OREGON INLET
WITH 13 FEET NEAR DUCK. SEAS WILL REMAIN AT CURRENT LEVELS THRU
TONIGHT THEN ONLY GRADUALLY SUBSIDE ON MONDAY AS WINDS BEGIN TO
DECREASE.
LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
AS OF 330 PM SUN...NLY WINDS DIMINISH TO LESS THAN 15 KT MON NIGHT
AS LOW PRES PUSHES EAST OF THE AREA AND HIGH PRES WEAKENS. SEAS
AS HIGH AS 6-8 FT NORTH AND 3-7 FT SOUTH EXPECTED TO START MON
NIGHT BUT ARE PROGGED TO DROP TO 5 FT OR LESS TUES MORNING. WINDS
THEN SHIFT TO SW TUES AND INCREASE TO 10-20 KT BY LATE IN THE DAY
AHEAD OF A COLD FRONT APPROACHING FROM THE NW. COULD SEE MINIMAL
SCA CONDITIONS DEVELOP TUES EVENING ACROSS THE CENTRAL WATERS AS
SEAS BUILD UP TO 6 FT IN SW FLOW AHEAD OF THE FRONT. THE FRONT
WILL CROSS THE WATERS TUES NIGHT WITH A NWLY SURGE AROUND 15-25 KT
LATE TUES NIGHT AND WED. SEAS FORECAST TO BUILD TO 4-7 FT NORTH OF
CAPE LOOKOUT LATE TUES NIGHT BRINGING SCA CONDITIONS ACROSS MUCH
OF THE WATERS...HOWEVER MODELS KEEP WINDS AROUND 15-20 KT WITH
SEAS AROUND 3-5 FT SOUTH OF CAPE LOOKOUT. HIGH PRES BUILDS INTO
THE AREA THURS AND FRI WITH SUB SCA CONDITIONS EXPECTED. WINDS DO
INCREASE THROUGH THE DAY FRI AHEAD OF THE NEXT COLD FRONT WITH SW
WINDS INCREASING TO 10-20 KT AND SEAS BUILDING TO 3-5 FT FRI
AFTERNOON AND EVENING.
&&
.TIDES/COASTAL FLOODING...
WAVES IN THE SURF ZONE WILL LIKELY REMAIN 8+ FT ON THE OUTER
BANKS NORTH OF CAPE HATTERAS...SO CONT HIGH SURF ADVRY THRU
TONIGHT INTO MONDAY. WATERS LEVELS CONTINUE 2 TO 3 FEET ABOVE
NORMAL SRN PAMLICO SOUND WITH PERSISTENT NE FLOW AND WILL BE
EXTENDING THE COASTAL FLOOD ADVISORY THROUGH THE DAY MONDAY.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...HIGH SURF ADVISORY UNTIL 2 PM EDT MONDAY FOR NCZ103.
COASTAL FLOOD ADVISORY UNTIL 8 PM EDT THIS EVENING FOR
NCZ093>095.
MARINE...SMALL CRAFT ADVISORY UNTIL 2 AM EDT MONDAY FOR AMZ136-137.
GALE WARNING UNTIL 2 AM EDT MONDAY FOR AMZ135-152-154-156-158.
SMALL CRAFT ADVISORY UNTIL 8 AM EDT MONDAY FOR AMZ130-131.
SMALL CRAFT ADVISORY UNTIL 7 AM EDT TUESDAY FOR AMZ150.
&&
$$
SYNOPSIS...BTC
NEAR TERM...CTC
SHORT TERM...BTC
LONG TERM...BTC/SK
AVIATION...CTC/SK/LEP
MARINE...CTC/BTC/SK
TIDES/COASTAL FLOODING...CTC/BTC
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
301 PM EDT SAT APR 19 2014
.SYNOPSIS...
WET WEATHER ASSOCIATED WITH AN OFFSHORE STORM SYSTEM WILL LAST
THROUGH TONIGHT AND INTO AT LEAST EARLY SUNDAY ALONG THE COAST.
AFTER A BRIEF PERIOD OF DRY WEATHER ON MONDAY...THE NEXT CHANCE
FOR RAIN WILL COME ON TUESDAY WITH A WEAK COLD FRONT. WARMING
TEMPERATURES ARE EXPECTED FOR THE LATTER PART OF NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 3:00 PM SATURDAY...BEAUTIFUL SATELLITE IMAGERY THIS AFTN AS AN
AREA OF LOW PRESSURE SPINS SLOWLY OFF THE NORTH-FLORIDA ATLANTIC
COAST. A TROUGH/COASTAL FRONT EXTENDING NE FROM THIS LOW PRESSURE TO
UP ALONG THE NC COAST...IS STRENGTHENING THIS AFTN...WHICH WILL HELP
ONCE AGAIN INCREASE RAINFALL ACROSS THE AREA. ADDITIONALLY...A RIDGE
OF HIGH PRESSURE ITS TRYING TO PUSH DOWN INTO THE
SOUTHEAST...DRIVING A PINCHED PRESSURE GRADIENT WHICH WILL SUPPORT
STRONG NE WINDS TONIGHT.
WELL RAINFALL THIS AFTN HAS NOT BE AS IMPRESSIVE AS ANY OF THE HIGH
RES GUIDANCE HAS BEEN SUGGESTING...MAKING IT DIFFICULT TO TRUST ANY
OF IT FOR THE REMAINDER OF THE NEAR TERM. BELIEVE THE RAIN HAS NOT
BEEN AS SIGNIFICANT DUE TO DRIER AIR ALOFT SW OF THE LOCAL
AREA...FROM WHICH THE BEST "MOIST" LIFT IS ORIGINATING. DRY
ISENTROPIC LIFT WILL NEVER CREATE SHOWERS...AND THUS ONLY CLOUDS AND
DRIZZLE HAVE BEEN ABLE TO PERSIST TODAY...DEVELOPING FROM THE
SATURATED NEAR-SURFACE LAYERS. THE GFS FORECAST SOUNDINGS BEST MATCH
THE OBSERVED SOUNDINGS FROM KCHS AND KFFC THIS MORNING...AND THUS IS
USED PREFERENTIALLY. LATEST KLTX RADAR DOES SHOW SHOWER ACTIVITY
REDEVELOPING ALONG THE COASTAL TROUGH JUST OFFSHORE...AND EXPECT
THIS TO BECOME MORE WIDESPREAD THIS EVENING AND TONIGHT...AND ADVECT
BACK TOWARDS THE COAST...ESPECIALLY THE CAPE FEAR REGION. HAVE
DECREASED POP FROM EARLIER...BUT STILL SHOW LIKELY POP ALONG THE
IMMEDIATE COAST TONIGHT...WITH LOW-CHC INLAND. AS THE NOCTURNAL
INVERSION DEVELOPS AND MOISTURE DOES WRAP BACK INTO THE AREA AROUND
THE LOW MOVING UP THE COAST...DRIZZLE/MIST MAY BECOME WIDESPREAD
ONCE AGAIN...AND COULD BE THE PREDOMINANT PRECIP MODE INLAND. AT THE
SAME TIME...THE INTERACTION OF THE LOW MOVING UP THE COAST AND THE
HIGH RIDGING DOWN FROM THE NORTH WILL DRIVE A TIGHTENING GRADIENT.
LLJ IS PROGGED TO RISE TO 40 KTS TONIGHT AT ONLY 1500 FT AGL...THUS
WIND GUSTS OF 25 TO 35 MPH WILL BECOME COMMON ACROSS THE
AREA...HIGHEST AT THE COAST.
TONIGHT...TEMPS WILL STRUGGLE TO FALL EVEN ON THE COOL NE FLOW. LOW
CLOUDS AND SHOWERS WILL KEEP DIURNAL RANGES LIMITED TO ONLY AROUND
10 DEGREES. THUS...EXPECT LOWS TONIGHT JUST ABOVE 50 AT THE
COAST...AND JUST BELOW 50 TOWARDS I-95.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 3:00 PM SATURDAY...GUIDANCE CONSISTENT IN DRIFTING
A VERTICALLY STACKED SYSTEM CURRENTLY MOVING OFFSHORE NORTHERN
FLORIDA TO THE NORTHEAST AND EVENTUALLY AWAY FROM THE EASTERN
CAROLINAS DURING THE SHORT TERM. MOISTURE PULLS AWAY WITH THE
SYSTEM...ALLOWING PRECIPITATION CHANCES TO GRADUALLY FADE FROM NW
TO SE DURING THE DAY ON SUNDAY. HIGHEST PRECIPITATION CHANCES WILL
BE SUNDAY MORNING AND ALONG THE COAST WHEN AND WHERE WE CAN EXPECT
LINGERING LIGHT RAIN OR DRIZZLE TO HANG ON BEFORE FADING DURING
THE AFTERNOON HOURS. OVERNIGHT SUNDAY AND MONDAY WILL BE DRY AS
RIDGING AT THE SURFACE AND ALOFT TRANSITS THE REGION FROM WEST TO
EAST.
GRADIENT ALONG BACKSIDE OF OFFSHORE SYSTEM WILL MAKE FOR A BREEZY
COUPLE OF DAYS...ESPECIALLY ON SUNDAY...WHEN WE WILL SEE NORTH TO
NORTHEASTERLY WINDS IN THE 15 TO 20 KT RANGE...IN ADDITION TO THE
HIGHER GUSTS.
COOL NORTHEASTERLY FLOW AND EXTENSIVE CLOUD COVER WILL KEEP SUNDAY
DAYTIME TEMPERATURES WELL BELOW NORMAL WITH HIGHS ONLY IN THE MID
60S. MONDAY WILL BE WARMER AS MORE SUNSHINE CAN BE EXPECTED...WITH
HIGHS OF RIGHT AROUND 70.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 3:00 PM SATURDAY...A SURFACE RIDGE AXIS OVER THE EASTERN
CAROLINAS ON TUESDAY WILL FADE AND SHIFT OFF THE COAST AHEAD OF A
COLD FRONT. MODELS HAVE BEEN CONSISTENT IN TIMING FROPA FOR TUESDAY
NIGHT. PREDOMINANTLY WESTERLY FLOW THROUGHOUT THE COLUMN IN ADVANCE
OF THE FRONT WILL SIGNIFICANTLY LIMIT MOISTURE AND THE COVERAGE OF
ANY ASSOCIATED CONVECTION IS EXPECTED TO REMAIN SCATTERED. SURFACE
HIGH PRESSURE WILL SHIFT OFFSHORE BY THE END OF THE WEEK AND A 500
MB RIDGE AXIS WILL TRAVERSE THE AREA FRIDAY. ALTHOUGH TEMPS
WON`T COOL DOWN MUCH BEHIND THE FRONT...THERE WILL BE A MODEST
UPWARD TREND IN TEMPS THU-SAT. WILL INTRODUCE A SMALL POP FRI-SAT
DUE TO MOISTURE RETURN AHEAD OF A WEAK SURFACE TROUGH APPROACHING
FROM THE WEST.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
AS OF 18Z...IFR CIGS ARE OCCURRING EARLY THIS AFTERNOON...BUT CIGS
AT KFLO/KLBT HAVE BEEN FLIRTING WITH MVFR AT TIMES. VSBYS ARE
VFR...BUT VSBYS AT KILM/KLBT HAVE BEEN MVFR/IFR IN -DZ -RA AND BR.
ALTHOUGH PRECIPITATION IS CURRENTLY DECREASING FROM S-N...SHOWERS
ARE REDEVELOPING TO THE SE OF KILM. THE LATEST HRRR SLINGS THIS NW
INTO KILM THEN KLBT THIS AFTERNOON. EXPECT A DECENT CHANCE OF
SHOWERS AT KILM/KLBT WITH VCSH ELSEWHERE THROUGH THE AFTERNOON.
EXPECT IFR CIGS TO CONTINUE AT THE COASTAL TERMINALS...WITH MVFR
VSBYS AT KILM DUE TO SHOWERS. EXPECT IFR CIGS INLAND AS WELL...WITH
TEMPO MVFR/IFR VSBYS AT KLBT DUE TO SHOWERS.
SHOWERS WILL INCREASE TONIGHT JUST OFFSHORE AS A SURFACE LOW MOVES
ENE WELL SOUTHEAST OF THE COASTAL TERMINALS. KLBT/KFLO SHOULD HAVE
THE LEAST POTENTIAL FOR RAIN WITH THE BEST POTENTIAL AT THE COASTAL
TERMINALS. AS THE ATTENDANT UPPER LOW PASSES EAST THE BEST RAIN
POTENTIAL SHOULD END AND CIGS IMPROVE TO MVFR 08-10Z. PERIODS OF VFR
COULD OCCUR BY 12Z BUT KEPT CIGS MVFR ATTM.
EXTENDED OUTLOOK...TEMPO MVFR CIGS SUNDAY...OTHERWISE VFR. VFR ON
MONDAY. CHANCE OF SHOWERS/TEMPO MVFR ON TUESDAY WITH A COLD FRONT.
VFR WEDNESDAY AND THURSDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 3:00 PM SATURDAY...GALE WARNING REMAINS IN EFFECT THROUGH
THE PERIOD. SLOW MOVING LOW PRESSURE NOW CENTERED JUST OFF THE
N-FL ATLANTIC COAST WILL GRADUALLY LIFT NE TONIGHT. AT THE SAME
TIME...A COASTAL TROUGH EXTENDING NE FROM THE PARENT LOW IS
STRENGTHENING OFF THE NC COAST...AND HAS DRIFTED SLIGHTLY EAST
SUCH THAT ALL COASTAL WATERS ARE NOW EXPERIENCING STRONG NE
WINDS...EVEN OUT TO FRYING PAN SHOALS. AS THIS LOW PRESSURE MOVES
CLOSER TONIGHT...AND HIGH PRESSURE TO THE NORTH CONTINUES TO RIDGE
INTO THE VICINITY...THE PRESSURE GRADIENT WILL ONLY STRENGTHEN.
THEREFORE...WINDS ARE EXPECTED TO RISE SIGNIFICANTLY
TONIGHT...BECOMING NE AT 20-30 KTS WITH GUSTS APPROACHING 40 KTS
TOWARDS SUNDAY MORNING. SEAS WILL RISE QUICKLY AS WELL...BECOMING
7-11 FT WITH A SHORT PERIOD NE WIND WAVE PREDOMINANT...FORCING
STEEP WAVE FACES. THE EXCEPTION WILL BE WITHIN THE WAVE SHADOWED
REGION SW OF BRUNSWICK COUNTY...WHERE WAVE HEIGHTS WILL REMAIN 2-4
FT.
SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 3:00 PM SATURDAY...PERIOD BEGINS WITH GALE WARNING FLAGS
FLYING AS THE TIGHT GRADIENT AROUND THE BACKSIDE OF AN OFFSHORE
SYSTEM WILL CRATE STRONG NORTHEASTERLY WINDS THROUGH AT LEAST THE
DAYLIGHT HOURS. SEAS MAY REACH AS HIGH AS 9 FT OVER THE OUTER
FRINGES OF OUR WATERS ON SUNDAY. CONDITIONS WILL GRADUALLY IMPROVE
SUNDAY NIGHT AND MONDAY AS THE OFFSHORE SYSTEM PULLS NORTHEAST AND
AWAY FROM THE COAST.
LONG TERM /TUESDAY THROUGH WEDNESDAY/...
AS OF 3:00 PM SATURDAY...WINDS WILL BECOME SW ON TUESDAY AHEAD OF A
COLD FRONT EXPECTED TO MOVE ACROSS THE WATERS LATE TUESDAY NIGHT.
NORTHERLY WINDS BEHIND THE FRONT WILL SURGE TO PERHAPS LOW-END SMALL
CRAFT ADVISORY LEVELS BEFORE THE GRADIENT WEAKENS BY MIDDAY.
DIRECTION WILL VEER TO THE SOUTHEAST BY THURSDAY AS THE CENTER OF
HIGH PRESSURE SLIDES OFFSHORE.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...GALE WARNING UNTIL 6 PM EDT SUNDAY FOR AMZ250-252-254-256.
&&
$$
SYNOPSIS...REK
NEAR TERM...JDW
SHORT TERM...REK
LONG TERM...CRM
AVIATION...MRR
MARINE...REK/JDW/CRM
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
130 PM EDT SAT APR 19 2014
.SYNOPSIS...
WET WEATHER ASSOCIATED WITH AN OFFSHORE STORM SYSTEM WILL LAST
THROUGH TONIGHT AND EVEN THROUGH SUNDAY ALONG THE COAST. THE NEXT
CHANCE FOR RAIN WILL COME TUESDAY WITH A WEAK COLD FRONT. WARMING
TEMPERATURES ARE EXPECTED FOR THE LATTER PART OF NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1030 AM SATURDAY...IMPRESSIVE STACKED LOW PRESSURE CENTERED
OVER NORTHERN FLORIDA WILL JUST DRIFT NORTHEAST TO OFF THE SC COAST
BY TONIGHT. AN ELONGATED TROUGH/COASTAL FRONT IS EXTENDING NE FROM
THIS LOW PRESSURE TO JUST OFF THE CAPE FEAR COAST...AND THIS
BOUNDARY WILL WAVER JUST OFFSHORE THROUGH THE NEAR TERM. A RIDGE OF
HIGH PRESSURE WILL PUSH DOWN TOWARDS THE AREA FROM THE MID-ATLANTIC
TODAY AS WELL. ALL OF THESE FEATURES TOGETHER WILL CREATE A
CONTINUED CLOUDY AND UNSETTLED DAY...WITH INCREASING NE WINDS.
THE WIDESPREAD HEAVY RAINFALL WHICH FELL ACROSS THE REGION THIS
MORNING HAS MOSTLY EXITED OFF TO THE NORTHEAST...WITH ONLY REMNANT
SHOWERS REMAINING LOCALLY. ALL AVAILABLE HIGH-RES GUIDANCE MODELS
THIS WELL...ALBEIT WITH A SLIGHTLY SLOWER PROGRESSION THAT WHAT IS
ACTUALLY BEING OBSERVED. HOWEVER...THESE SAME MODELS SUGGEST THAT
HEAVIER RAIN WILL ONCE AGAIN OVERSPREAD THE AREA THIS EVENING AND
TONIGHT...AS MOISTURE CONTINUES TO WRAP ONTO THE COAST AHEAD OF THE
LOW PRESSURE SYSTEM TO THE SOUTH. MODEL SOUNDINGS ARE QUITE
SATURATED...MUCH MORESO THAN 12Z OBSERVED SOUNDINGS TO THE
SOUTH...WHICH SHOW PRONOUNCED DRY AIR ABOVE 700MB. EXPECT THIS DRY
AIR IS DUE TO THE RIDGE MOVING SOUTH AND SOME SUBSIDENCE BEHIND THE
INITIAL WAVE OF PRECIP...BUT CONTINUED LOW-LEVEL SATURATION WILL
DRIVE OVERCAST SKY COVER AND PERIODIC SHOWERS/DRIZZLE THROUGH THE
AFTN. BY THIS EVENING...COLUMN WILL ONCE AGAIN SATURATE AND MORE
WIDESPREAD SHOWERS WITH HEAVIER RAINFALL IS EXPECTED. AN ADDITIONAL
ONE HALF TO ONE INCH OF QPF IS POSSIBLE AS SHOWN VIA THE 09Z SREF
PLUMES...HIGHEST ALONG THE CAPE FEAR COAST...WHERE RAINFALL OF 2-4"
HAS ALREADY FALLEN SINCE LAST NIGHT.
IN ADDITION TO THE INCREASE IN RAINFALL THIS EVE...NE WINDS WILL
GRADUALLY INCREASE AS WELL AS THE PRESSURE GRADIENT TIGHTENS.
ALTHOUGH MIXING WILL REMAIN SHALLOW...NE WIND GUSTS OF 30 MPH ARE
EXPECTED TO BECOME COMMON TONIGHT...WITH ISOLATED GUSTS TO 40 MPH
POSSIBLE ALONG THE COAST. WHILE THIS WILL FALL BELOW WI.Y
THRESHOLDS...MAY HAVE TO CONSIDER AN SPS FOR ISOLATED WIND
IMPACTS...INCLUDING TREE DAMAGE ON THE SATURATED GROUND...WITH THE
AFTN PACKAGE.
TEMPS TODAY WILL BARELY MOVE THANKS TO THE COOL NE WINDS AND CLOUD
COVER...AND EXPECT HIGHS ONLY IN THE MID 50S MOST PLACES...BUT SOME
LOW 60S ARE LIKELY ALONG THE SOUTHERN GRAND STRAND NEAR THE SOUTH
SANTEE RIVER. DIURNAL RANGES WILL ALSO BE LIMITED...AND THUS MINS
TONIGHT WILL FALL ONLY INTO THE LOW 50S...WITH SOME UPPER 40S WELL
INLAND.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 300 AM SATURDAY...MOISTURE FROM THE NEAR TERM STORM SYSTEM TO
LINGER INTO SUNDAY. THE MAIN FORECAST ISSUE THEN IS HOW FAR INLAND
RAIN MANAGES TO SPREAD AND WHAT THE AMOUNTS END UP LOOKING LIKE.
THIS SYSTEM WILL ALSO BRING VERY BREEZY CONDITIONS TO THE COAST THAT
MAY APPROACH WIND ADVISORY LEVELS ESPECIALLY IF SSTS DO NOT INHIBIT
VERTICAL MIXING IN THE STRONG ONSHORE JETTING. BL FLOW BACKS SUNDAY
NIGHT ALLOWING FOR LESS OF AN INLAND PUSH OF MOISTURE. SOME LOW RAIN
CHANCES MAY PERSIST ALONG THE IMMEDIATE COAST BUT THATS ABOUT IT.
MONDAY BRINGS MID LEVEL RIDGING/DRYING. THE LOW LEVEL MOISTURE MAY
BE SLOW TO ERODE FROM THE EASTERN ZONES HOWEVER ESPECIALLY IF THE
INVERSION SHOWN IN GFS MODEL SOUNDINGS DEVELOPS TO HELP TRAP IT.
THIS FEATURE DOES NOT APPEAR IN WRF MODEL SOUNDINGS.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 300 AM SATURDAY...COLD FRONT APPROACHES ON TUESDAY BRINGING
SOME LOW RAIN CHANCES ON ACCOUNT OF LIMITED PREFRONTAL MOISTURE
FLUX. HEIGHT RISES ARE QUICK TO FOLLOW THE BOUNDARY OFFSETTING ANY
LOW LEVEL COOL ADVECTION...WHICH THERE DOESNT SEEM TO BE MUCH OF
ANYWAY. LATE WEEK TEMPS TO STAY ON THE WARM SIDE OF CLIMO AS MID
LEVEL RIDGE BUILDS AND SURFACE HIGH ONLY VERY SLOWLY MIGRATES
EASTWARD.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
AS OF 18Z...IFR CIGS ARE OCCURRING EARLY THIS AFTERNOON...BUT CIGS
AT KFLO/KLBT HAVE BEEN FLIRTING WITH MVFR AT TIMES. VSBYS ARE
VFR...BUT VSBYS AT KILM/KLBT HAVE BEEN MVFR/IFR IN -DZ -RA AND BR.
ALTHOUGH PRECIPITATION IS CURRENTLY DECREASING FROM S-N...SHOWERS
ARE REDEVELOPING TO THE SE OF KILM. THE LATEST HRRR SLINGS THIS NW
INTO KILM THEN KLBT THIS AFTERNOON. EXPECT A DECENT CHANCE OF
SHOWERS AT KILM/KLBT WITH VCSH ELSEWHERE THROUGH THE AFTERNOON.
EXPECT IFR CIGS TO CONTINUE AT THE COASTAL TERMINALS...WITH MVFR
VSBYS AT KILM DUE TO SHOWERS. EXPECT IFR CIGS INLAND AS WELL....WITH
TEMPO MVFR/IFR VSBYS AT KLBT DUE TO SHOWERS.
SHOWERS WILL INCREASE TONIGHT JUST OFFSHORE AS A SURFACE LOW MOVES
ENE WELL SOUTHEAST OF THE COASTAL TERMINALS. KLBT/KFLO SHOULD HAVE
THE LEAST POTENTIAL FOR RAIN WITH THE BEST POTENTIAL AT THE COASTAL
TERMINALS. AS THE ATTENDANT UPPER LOW PASSES EAST THE BEST RAIN
POTENTIAL SHOULD END AND CIGS IMPROVE TO MVFR 08-10Z. PERIODS OF VFR
COULD OCCUR BY 12Z BUT KEPT CIGS MVFR ATTM.
EXTENDED OUTLOOK...TEMPO MVFR CIGS SUNDAY...OTHERWISE VFR. VFR ON
MONDAY. CHANCE OF SHOWERS/TEMPO MVFR ON TUESDAY WITH A COLD FRONT.
VFR WEDNESDAY AND THURSDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1030 AM SATURDAY...GALE WARNING REMAINS IN EFFECT THROUGH THE
PERIOD. SLOW MOVING LOW PRESSURE ACROSS NORTHERN FLORIDA IS DRAPING
A COASTAL FRONT NE INTO THE LOCAL COASTAL WATERS. THIS LOW WILL
DRIFT NORTHEAST TODAY...WHILE A RIDGE OF HIGH PRESSURE ATTEMPTS TO
STRENGTHEN DOWN THE COAST. THESE TWO FEATURES IN TANDEM WILL DRIVE A
TIGHTENING PRESSURE GRADIENT...AND WINDS WILL INCREASE THROUGH
TODAY...AND ESPECIALLY TONIGHT. CURRENT OBS SHOW THAT THE WEAKEST
WINDS ARE...SURPRISINGLY...AT FRYING PAN SHOALS WHICH IS SE OF THE
COASTAL FRONT AND THUS EXPERIENCING THE WEAKEST GRADIENT. BUOYS
41036...41037...AND 41038 ARE ALL WEST OF THE FRONT...AND HAVE NE
WINDS OF 20-30 KTS THIS MORNING. THESE NE WINDS WILL ONLY STRENGTHEN
THROUGH TONIGHT...SO EVEN THOUGH GALE CONDITIONS ARE NOT BEING MET
YET...THERE IS HIGH CONFIDENCE THAT THEY WILL BE LATER TODAY AND
TONIGHT. SEAS WILL CONTINUE TO GROW ON THE HIGHER WINDS...RISING
FROM THE CURRENT 4-7 FT...TO AS MUCH AS 7-10 FT TONIGHT...WITH 12+
FT EXPECTED AT FRYING PAN SHOALS. THE EXCEPTION TO THIS WILL BE IN
THE TYPICAL WAVE SHADOW REGION ALONG THE BRUNSWICK COUNTY
COAST...WHERE 2-4 FT SEAS WILL BE PREDOMINANT.
SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 300 AM SATURDAY...VERY UNSETTLED WITH FLAGS IN PLACE FOR THE
ENTIRE PERIOD. THOSE FLAGS LIKELY IN THE FORM OF GALE WARNING EARLY
IN THE PERIOD AND THERE IS JUST ENOUGH MODEL DIFFERENCES TO ERODE
CONFIDENCE AS TO WHEN THAT WILL LOWER TO SMALL CRAFT
ADVISORY...COULD BE DURING THE DAY SUNDAY OR NOT UNTIL SUNDAY NIGHT.
MEANWHILE WAVES REMAIN VERY STEEP AND LARGE. ABATING TREND ON MONDAY
SHOULD DROP WINDS BELOW ADVISORY THRESHOLDS ALTHOUGH THE LAGGING
SEAS COULD MAKE IT UNTIL LATE DAY WHEN FLAGS ARE LOWERED.
LONG TERM /TUESDAY THROUGH WEDNESDAY/...
AS OF 300 AM SATURDAY...BACKING WIND ON TUESDAY ASSOC WITH THE
APPROACH OF A COLD FRONT FROM THE NW. A SHARP VEER TO OFFSHORE ON
TUESDAY NIGHT WITH FROPA MAY ALSO BE ACCOMPANIED BY A BRIEF SURGE
THAT COULD NECESSITATE A BRIEF ADVISORY BUT THINGS LOOK TO SETTLE
PRETTY QUICKLY HEADING INTO WEDNESDAY. THE COOL AIR HAS TROUBLE
MAKING IT THIS FAR SOUTH AND THUS THERE IS NO BIG PUSH OF HIGH
PRESSURE...THE CENTER OF WHICH REMAINS OVER THE GREAT LAKES. IT WILL
HOWEVER DROP SOUTH AND EAST BY THURSDAY AND BE FOUND CENTERED UP AND
DOWN MUCH OF THE EAST COAST.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...GALE WARNING UNTIL 6 PM EDT SUNDAY FOR AMZ250-252-254-256.
&&
$$
NEAR TERM...JDW
SHORT TERM...MBB
LONG TERM...MBB
AVIATION...MRR/JDW
AREA FORECAST DISCUSSION
NWS RALEIGH NC
740 AM EDT SAT APR 19 2014
.SYNOPSIS...LOW PRESSURE OVER THE NORTHEASTERN GULF OF MEXICO THIS
MORNING WILL DRIFT VERY SLOWLY ALONG THE SOUTHEAST US COAST THROUGH
THE WEEKEND.
&&
.NEAR TERM /THROUGH SUNDAY NIGHT/...
AS OF 305 AM SATURDAY...
FOR TODAY/TONIGHT: THE MOST DREARY WEATHER OF THE WEEKEND WILL OCCUR
IN THE NEXT 12-18 HOURS... WITH CERTAIN RAIN FOR ALL. THE LATEST
SURFACE AND UPPER AIR ANALYSES SHOW THE RESPECTIVE LOW CENTERS OVER
NE FL AND SRN AL... SHIFTING VERY SLOWLY EASTWARD. THE SURFACE HIGH
TO OUR NNE OVER DELMARVA-NJ THAT IS SUPPLYING THE CHILLY NE FLOW IS
POISED TO BE SUPPLANTED BY A LARGER AND COLDER HIGH NOW CENTERED
OVER ONTARIO... WHICH WILL BE USHERED INTO OUR REGION THANKS TO A
WEAK NRN STREAM FRONT EXTENDING FROM UPSTATE NY THROUGH THE OH
VALLEY AND PUSHING TO THE ESE... ATTENDING A SWIFT-MOVING MID LEVEL
TROUGH. IDEALLY JUXTAPOSED UPPER JET CORES ON THE EAST SIDE OF THIS
TROUGH (RIGHT REAR QUAD OVER NC) AND ON THE EAST SIDE OF THE VORTEX
OVER AL (LEFT FRONT QUAD OVER NC) HAVE STRENGTHENED THE UPPER
DIVERGENCE OVER NC... SUPPORTING A BROAD SWATH OF MOSTLY LIGHT-MDT
RAIN OVER NC. WITH ABUNDANT MID LEVEL MOISTURE IN PLACE AND THIS
UPPER LEVEL FORCING FOR ASCENT COMBINED WITH MID LEVEL DEFORMATION
AND MASS CONVERGENCE AROUND 850 MB SHOULD CONTINUE TO GENERATE
WIDESPREAD RAIN THROUGH THIS MORNING. LARGE SCALE MODELS DEPICT THE
BEST LIFT IN A BAND ACROSS THE SW PORTION OF CENTRAL NC... WHERE THE
UPPER DIVERGENCE AND LOW LEVEL CONVERGENCE WILL BE WELL CORRELATED
IN THE VERTICAL... AND THIS IS INDICATED AS WELL BY SREF
PROBABILITIES AND THE LATEST HRRR RUNS. THIS AREA COULD SEE UP TO AN
ADDITIONAL 1.0-1.5 INCHES OF RAIN... MOST FALLING THIS MORNING.
LATEST OBSERVED RAINFALL SO FAR RANGES FROM JUST A FEW HUNDREDTHS
NEAR THE VA BORDER TO JUST UNDER AN INCH IN THE FAR SOUTH (SCOTLAND
TO SAMPSON CO)... WITH AREAS FROM THE TRIANGLE ACROSS THE SOUTHWEST
CWA SEEING AROUND 0.30-0.40 INCH SO FAR. WHILE THE FLASH FLOOD
GUIDANCE IS LOWEST IN THIS SW QUADRANT OF THE FORECAST AREA (AROUND
1.75" IN 1 HR)... THE ADDITIONAL RAINFALL IS EXPECTED TO BE LIGHT
ENOUGH SUCH THAT THIS RATE WON`T BE ACHIEVED. BUT A GRAND TOTAL OF 2
INCHES OR MORE OF RAIN IN THIS AREA COULD LEAD TO SOME STREET
FLOODING ESPECIALLY IN THOSE VULNERABLE AREAS NEAR CREEKS AND IN
TOWNS. THEN BY THIS AFTERNOON... THE AFOREMENTIONED WEAK NRN STREAM
FRONT WILL HAVE ALLOWED THE CHILLIER HIGH TO BUILD SOUTHWARD INTO NC
AS IT CROSSES SRN QUEBEC AND THE ST LAWRENCE VALLEY THROUGH
TONIGHT... HELPING TO DRY OUT THE LOW LEVELS OVER NC FROM THE NORTH.
ALSO LATER TODAY THE UPPER LEVELS WILL GRADUALLY DRY OUT AS THE DRY
SLOT ALOFT PUNCHES IN FROM THE SOUTH... AND THIS DRYING ABOVE 0C
SHOULD LEAD TO A SLOW TREND TO MOSTLY LIGHT PATCHY DRIZZLE... WITH
THE TRANSITION LAST TO OCCUR OVER THE NW PIEDMONT WHERE THE
DEFORMATION BAND WILL MOST LONG-LIVED. SO... IN TERMS OF SENSIBLE
WEATHER... WILL START THE DAY WITH 100% POPS... GRADUALLY TRENDING
DOWN TO GOOD CHANCES OF RAIN OR DRIZZLE DURING THE LATE AFTERNOON AS
THE CHANCES FOR MEASURABLE PRECIP DROP. MODELS DISAGREE ON EXACTLY
WHERE AND HOW MUCH PRECIP THERE MIGHT BE TONIGHT... BUT BASED ON THE
LARGE SCALE PATTERN... WILL KEEP A LOW CHANCE OF LIGHT RAIN LATE
TONIGHT OVER THE SOUTHEAST... WHERE ONSHORE-DIRECTED FLOW WILL LAST
THE LONGEST. TEMPS ARE CHALLENGING TO SAY THE LEAST... WITH SOME
STATISTICAL GUIDANCE APPEARING OVERLY OPTIMISTIC GIVEN THE
WIDESPREAD CLOUDS AND RAIN FOR MUCH OF THE DAY. HAVE FOLLOWED HIGH-
RES AND RAPID-UPDATE GUIDANCE INCLUDING THE LOCAL WRF / HRRR / RAP /
GRIDDED LAMP FOR TEMPS TODAY... GIVING HIGHS FROM THE MID 50S IN THE
SOUTH TO UPPER 50S IN THE FAR NORTHWEST. EXPECT CLOUDS TO LINGER
THROUGH TONIGHT... BUT WITH RAIN/DRIZZLE DWINDLING ESPECIALLY FROM
NW TO SE. LOWS 45-50.
FOR SUN/SUN NIGHT: THE MID LEVEL LOW IS EXPECTED TO SHIFT SLOWLY OFF
SAVANNAH EARLY SUN THEN SLOWLY FILL AS IT HEADS ESE THROUGH SUN
NIGHT. MODELS INDICATE ABUNDANT MOISTURE HANGING ON IN THE 850-700
MB LAYER OVER NC SUNDAY... WITH A PERSISTENT COOL AND BRISK
NORTHEAST LOW LEVEL FLOW FEEDING IN FROM THE CHILLY BUT PROGRESSIVE
AND MODIFYING SURFACE HIGH TO OUR NE. LOW LEVEL THICKNESSES ARE
EXPECTED TO BE AROUND 15-20 M BELOW NORMAL... INDICATING HIGHS
NEARLY 2 CATEGORIES BELOW NORMAL. EXPECT HIGHS OF 64-68... WITH
PARTIAL SUNSHINE LATE IN THE DAY AS MID LEVEL RIDGING STARTS TO
BUILD IN FROM THE WEST. CLEARING SKIES SUN NIGHT... ALTHOUGH THERE
MAY BE ENOUGH RESIDUAL MOISTURE IN THE NORTHEAST CWA WITH A
CONTINUED ATLANTIC FETCH TO BRING ABOUT PATCHY LOW STRATUS
DEVELOPMENT OVERNIGHT. LOWS 40-47. -GIH
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 255 AM SATURDAY...
THE SLOW MOVING CUT OFF LOW IMPACTING THE REGION THIS WEEKEND IS
FORECAST TO BE EAST OF THE CAROLINAS SUNDAY NIGHT...WITH AN
ELONGATED SURFACE RIDGE EXTENDING FROM THE MID-ATLANTIC STATES INTO
THE NC. AS THE LOW MOVES OFF TO THE NORTHEAST...WINDS SHOULD BACK
AROUND TO MORE NORTHERLY THAN NORTHEASTERLY AND ALLOW SOME DRIER AIR
TO WORK INTO CENTRAL NC FROM THE NORTH. THE NAM ISNT QUITE AS DRY
AS THE GFS AND ECMWF...SHOWING SOME MOISTURE LINGERING AROUND 850MB
EAST OF I-95. WHILE THE AIRMASS WONT BEGIN TO MODERATE SIGNIFICANTLY
UNTIL TUESDAY...STRONGER HEATING SHOULD SUPPORT HIGHS REACHING THEIR
POTENTIAL OF UPPER 60S AND LOWER 70S.
A PROGRESSIVE TROUGH MOVING THROUGH THE CENTRAL US WILL APPROACH THE
REGION MONDAY NIGHT AND EARLY TUESDAY...WITH THE ASSOCIATED FRONTAL
ZONE PROJECTED TO CROSS CENTRAL NC TUESDAY AFTERNOON AND EVENING.
AHEAD OF THE SYSTEM...LOWS WILL BE MUCH MORE MILD MONDAY NIGHT WITH
INCREASING MID/HIGH CLOUDS AND A WEAK RETURN FLOW ACROSS THE WESTERN
PIEDMONT. LOWS IN THE LOWER 50S WEST AND UPPER 40S EAST. SOUTH TO
SOUTHWESTERLY FLOW WILL INCREASE ON TUESDAY AHEAD OF THE APPROACHING
FRONT. MODELS CURRENTLY FORECAST A DEWPOINT RECOVERY INTO THE MID
AND UPPER 50S...WHICH COMBINED WITH HIGHS IN THE UPPER 70S TO AROUND
80 AND WEAK MID-LEVEL LAPSE RATES WOULD SUGGEST WEAK
INSTABILITY...MAINLY ACROSS THE WEST. MODEST SHEAR MAY SUPPORT A
FEW STRONG STORMS...BUT WITHOUT BETTER UPPER SUPPORT THE THREAT OF
SEVERE WEATHER LOOKS ISOLATED AT THIS POINT.
&&
.LONG TERM /WEDNESDAY THROUGH FRIDAY/...
AS OF 255 AM SATURDAY...
BEHIND TUESDAYS SYSTEM...CANADIAN HIGH PRESSURE WILL BUILD ACROSS
MUCH OF THE EASTERN US ON WEDNESDAY AND THURSDAY. THURSDAY LOOKS TO
BE THE COOLEST DAY AS THICKNESSES FALL BACK BELOW NORMAL...WITH
HIGHS MAYBE 5-10 DEGREES BELOW NORMAL...BUT THEN QUICKLY REBOUND ON
FRIDAY AS ANOTHER PROGRESSIVE UPPER TROUGH APPROACHES FROM THE WEST.
THIS NEXT SYSTEM RESEMBLES THE EARLY WEAK SYSTEM...THOUGH
POTENTIALLY WITH A LITTLE MORE MOISTURE AVAILABLE FROM THE GULF.
THE CURRENT FORECAST WILL REMAIN DRY...WITH THE BETTER CHANCE OF
PRECIP JUST BEYOND THE END OF THE FORECAST ON FRIDAY NIGHT AND
SATURDAY.
&&
.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
AS OF 740 AM SATURDAY...
AN EXPANSIVE STORM SYSTEM CENTERED ON THE FL GULF COAST WILL AFFECT
THE SOUTHEAST STATES AND CAROLINAS THROUGHOUT TODAY AND TONIGHT.
FAIRLY WIDESPREAD LIGHT RAIN HAS LINGERED THROUGH THE NIGHT... BUT
VSBYS HAVE VASCILLATED AMONG VFR / MVFR / IFR THROUGH THE NIGHT.
CIGS ARE LIKELY TO VARY BETWEEN VFR AND MVFR (AS MVFR CLOUDS SHIFT
FROM SCT TO BKN AND BACK TO SCT AGAIN) THROUGHOUT THE DAY.
UNFORTUNATELY... CONFIDENCE IN THE OCCURRENCE OF MVFR CONDITIONS AT
ANY PARTICULAR TIME TODAY IS VERY LOW. VSBYS MAY BRIEFLY DROP TO
MVFR IN ANY HEAVIER RAIN BANDS THROUGH 19Z. AFTER AROUND 19-21Z AT
INT/GSO/RWI/RDU... CIGS ARE EXPECTED TO IMPROVE TO PREVAILING VFR AS
DRIER LOW LEVEL AIR NOSES IN FROM HIGH PRESSURE TO THE NORTH... WITH
JUST PATCHY DRIZZLE AT MOST FROM 21Z THROUGH THE END OF THE TAF
VALID PERIOD (12Z SUN). EXPECT IMPROVEMENT TO MVFR AT FAY 06Z-09Z.
LOOKING BEYOND 12Z SUN... EXPECT IMPROVEMENT AT FAY TO VFR BY 12Z.
EXPECT VFR CONDITIONS TO DOMINATE THROUGH MON NIGHT. PASSAGE OF A
MID LEVEL TROUGH AND SURFACE COLD FRONT FROM THE NW WILL BRING A
RISK OF SUB-VFR CONDITIONS TUE/TUE NIGHT. VFR CONDITIONS RETURN FOR
WED. -GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...SMITH
NEAR TERM...HARTFIELD
SHORT TERM...SMITH
LONG TERM...SMITH
AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS RALEIGH NC
305 AM EDT SAT APR 19 2014
.SYNOPSIS...LOW PRESSURE OVER THE NORTHEASTERN GULF OF MEXICO THIS
MORNING WILL DRIFT VERY SLOWLY ALONG THE SOUTHEAST US COAST THROUGH
THE WEEKEND.
&&
.NEAR TERM /THROUGH SUNDAY NIGHT/...
AS OF 305 AM SATURDAY...
FOR TODAY/TONIGHT: THE MOST DREARY WEATHER OF THE WEEKEND WILL OCCUR
IN THE NEXT 12-18 HOURS... WITH CERTAIN RAIN FOR ALL. THE LATEST
SURFACE AND UPPER AIR ANALYSES SHOW THE RESPECTIVE LOW CENTERS OVER
NE FL AND SRN AL... SHIFTING VERY SLOWLY EASTWARD. THE SURFACE HIGH
TO OUR NNE OVER DELMARVA-NJ THAT IS SUPPLYING THE CHILLY NE FLOW IS
POISED TO BE SUPPLANTED BY A LARGER AND COLDER HIGH NOW CENTERED
OVER ONTARIO... WHICH WILL BE USHERED INTO OUR REGION THANKS TO A
WEAK NRN STREAM FRONT EXTENDING FROM UPSTATE NY THROUGH THE OH
VALLEY AND PUSHING TO THE ESE... ATTENDING A SWIFT-MOVING MID LEVEL
TROUGH. IDEALLY JUXTAPOSED UPPER JET CORES ON THE EAST SIDE OF THIS
TROUGH (RIGHT REAR QUAD OVER NC) AND ON THE EAST SIDE OF THE VORTEX
OVER AL (LEFT FRONT QUAD OVER NC) HAVE STRENGTHENED THE UPPER
DIVERGENCE OVER NC... SUPPORTING A BROAD SWATH OF MOSTLY LIGHT-MDT
RAIN OVER NC. WITH ABUNDANT MID LEVEL MOISTURE IN PLACE AND THIS
UPPER LEVEL FORCING FOR ASCENT COMBINED WITH MID LEVEL DEFORMATION
AND MASS CONVERGENCE AROUND 850 MB SHOULD CONTINUE TO GENERATE
WIDESPREAD RAIN THROUGH THIS MORNING. LARGE SCALE MODELS DEPICT THE
BEST LIFT IN A BAND ACROSS THE SW PORTION OF CENTRAL NC... WHERE THE
UPPER DIVERGENCE AND LOW LEVEL CONVERGENCE WILL BE WELL CORRELATED
IN THE VERTICAL... AND THIS IS INDICATED AS WELL BY SREF
PROBABILITIES AND THE LATEST HRRR RUNS. THIS AREA COULD SEE UP TO AN
ADDITIONAL 1.0-1.5 INCHES OF RAIN... MOST FALLING THIS MORNING.
LATEST OBSERVED RAINFALL SO FAR RANGES FROM JUST A FEW HUNDREDTHS
NEAR THE VA BORDER TO JUST UNDER AN INCH IN THE FAR SOUTH (SCOTLAND
TO SAMPSON CO)... WITH AREAS FROM THE TRIANGLE ACROSS THE SOUTHWEST
CWA SEEING AROUND 0.30-0.40 INCH SO FAR. WHILE THE FLASH FLOOD
GUIDANCE IS LOWEST IN THIS SW QUADRANT OF THE FORECAST AREA (AROUND
1.75" IN 1 HR)... THE ADDITIONAL RAINFALL IS EXPECTED TO BE LIGHT
ENOUGH SUCH THAT THIS RATE WON`T BE ACHIEVED. BUT A GRAND TOTAL OF 2
INCHES OR MORE OF RAIN IN THIS AREA COULD LEAD TO SOME STREET
FLOODING ESPECIALLY IN THOSE VULNERABLE AREAS NEAR CREEKS AND IN
TOWNS. THEN BY THIS AFTERNOON... THE AFOREMENTIONED WEAK NRN STREAM
FRONT WILL HAVE ALLOWED THE CHILLIER HIGH TO BUILD SOUTHWARD INTO NC
AS IT CROSSES SRN QUEBEC AND THE ST LAWRENCE VALLEY THROUGH
TONIGHT... HELPING TO DRY OUT THE LOW LEVELS OVER NC FROM THE NORTH.
ALSO LATER TODAY THE UPPER LEVELS WILL GRADUALLY DRY OUT AS THE DRY
SLOT ALOFT PUNCHES IN FROM THE SOUTH... AND THIS DRYING ABOVE 0C
SHOULD LEAD TO A SLOW TREND TO MOSTLY LIGHT PATCHY DRIZZLE... WITH
THE TRANSITION LAST TO OCCUR OVER THE NW PIEDMONT WHERE THE
DEFORMATION BAND WILL MOST LONG-LIVED. SO... IN TERMS OF SENSIBLE
WEATHER... WILL START THE DAY WITH 100% POPS... GRADUALLY TRENDING
DOWN TO GOOD CHANCES OF RAIN OR DRIZZLE DURING THE LATE AFTERNOON AS
THE CHANCES FOR MEASURABLE PRECIP DROP. MODELS DISAGREE ON EXACTLY
WHERE AND HOW MUCH PRECIP THERE MIGHT BE TONIGHT... BUT BASED ON THE
LARGE SCALE PATTERN... WILL KEEP A LOW CHANCE OF LIGHT RAIN LATE
TONIGHT OVER THE SOUTHEAST... WHERE ONSHORE-DIRECTED FLOW WILL LAST
THE LONGEST. TEMPS ARE CHALLENGING TO SAY THE LEAST... WITH SOME
STATISTICAL GUIDANCE APPEARING OVERLY OPTIMISTIC GIVEN THE
WIDESPREAD CLOUDS AND RAIN FOR MUCH OF THE DAY. HAVE FOLLOWED HIGH-
RES AND RAPID-UPDATE GUIDANCE INCLUDING THE LOCAL WRF / HRRR / RAP /
GRIDDED LAMP FOR TEMPS TODAY... GIVING HIGHS FROM THE MID 50S IN THE
SOUTH TO UPPER 50S IN THE FAR NORTHWEST. EXPECT CLOUDS TO LINGER
THROUGH TONIGHT... BUT WITH RAIN/DRIZZLE DWINDLING ESPECIALLY FROM
NW TO SE. LOWS 45-50.
FOR SUN/SUN NIGHT: THE MID LEVEL LOW IS EXPECTED TO SHIFT SLOWLY OFF
SAVANNAH EARLY SUN THEN SLOWLY FILL AS IT HEADS ESE THROUGH SUN
NIGHT. MODELS INDICATE ABUNDANT MOISTURE HANGING ON IN THE 850-700
MB LAYER OVER NC SUNDAY... WITH A PERSISTENT COOL AND BRISK
NORTHEAST LOW LEVEL FLOW FEEDING IN FROM THE CHILLY BUT PROGRESSIVE
AND MODIFYING SURFACE HIGH TO OUR NE. LOW LEVEL THICKNESSES ARE
EXPECTED TO BE AROUND 15-20 M BELOW NORMAL... INDICATING HIGHS
NEARLY 2 CATEGORIES BELOW NORMAL. EXPECT HIGHS OF 64-68... WITH
PARTIAL SUNSHINE LATE IN THE DAY AS MID LEVEL RIDGING STARTS TO
BUILD IN FROM THE WEST. CLEARING SKIES SUN NIGHT... ALTHOUGH THERE
MAY BE ENOUGH RESIDUAL MOISTURE IN THE NORTHEAST CWA WITH A
CONTINUED ATLANTIC FETCH TO BRING ABOUT PATCHY LOW STRATUS
DEVELOPMENT OVERNIGHT. LOWS 40-47. -GIH
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 255 AM SATURDAY...
THE SLOW MOVING CUT OFF LOW IMPACTING THE REGION THIS WEEKEND IS
FORECAST TO BE EAST OF THE CAROLINAS SUNDAY NIGHT...WITH AN
ELONGATED SURFACE RIDGE EXTENDING FROM THE MID-ATLANTIC STATES INTO
THE NC. AS THE LOW MOVES OFF TO THE NORTHEAST...WINDS SHOULD BACK
AROUND TO MORE NORTHERLY THAN NORTHEASTERLY AND ALLOW SOME DRIER AIR
TO WORK INTO CENTRAL NC FROM THE NORTH. THE NAM ISNT QUITE AS DRY
AS THE GFS AND ECMWF...SHOWING SOME MOISTURE LINGERING AROUND 850MB
EAST OF I-95. WHILE THE AIRMASS WONT BEGIN TO MODERATE SIGNIFICANTLY
UNTIL TUESDAY...STRONGER HEATING SHOULD SUPPORT HIGHS REACHING THEIR
POTENTIAL OF UPPER 60S AND LOWER 70S.
A PROGRESSIVE TROUGH MOVING THROUGH THE CENTRAL US WILL APPROACH THE
REGION MONDAY NIGHT AND EARLY TUESDAY...WITH THE ASSOCIATED FRONTAL
ZONE PROJECTED TO CROSS CENTRAL NC TUESDAY AFTERNOON AND EVENING.
AHEAD OF THE SYSTEM...LOWS WILL BE MUCH MORE MILD MONDAY NIGHT WITH
INCREASING MID/HIGH CLOUDS AND A WEAK RETURN FLOW ACROSS THE WESTERN
PIEDMONT. LOWS IN THE LOWER 50S WEST AND UPPER 40S EAST. SOUTH TO
SOUTHWESTERLY FLOW WILL INCREASE ON TUESDAY AHEAD OF THE APPROACHING
FRONT. MODELS CURRENTLY FORECAST A DEWPOINT RECOVERY INTO THE MID
AND UPPER 50S...WHICH COMBINED WITH HIGHS IN THE UPPER 70S TO AROUND
80 AND WEAK MID-LEVEL LAPSE RATES WOULD SUGGEST WEAK
INSTABILITY...MAINLY ACROSS THE WEST. MODEST SHEAR MAY SUPPORT A
FEW STRONG STORMS...BUT WITHOUT BETTER UPPER SUPPORT THE THREAT OF
SEVERE WEATHER LOOKS ISOLATED AT THIS POINT.
&&
.LONG TERM /WEDNESDAY THROUGH FRIDAY/...
AS OF 255 AM SATURDAY...
BEHIND TUESDAYS SYSTEM...CANADIAN HIGH PRESSURE WILL BUILD ACROSS
MUCH OF THE EASTERN US ON WEDNESDAY AND THURSDAY. THURSDAY LOOKS TO
BE THE COOLEST DAY AS THICKNESSES FALL BACK BELOW NORMAL...WITH
HIGHS MAYBE 5-10 DEGREES BELOW NORMAL...BUT THEN QUICKLY REBOUND ON
FRIDAY AS ANOTHER PROGRESSIVE UPPER TROUGH APPROACHES FROM THE WEST.
THIS NEXT SYSTEM RESEMBLES THE EARLY WEAK SYSTEM...THOUGH
POTENTIALLY WITH A LITTLE MORE MOISTURE AVAILABLE FROM THE GULF.
THE CURRENT FORECAST WILL REMAIN DRY...WITH THE BETTER CHANCE OF
PRECIP JUST BEYOND THE END OF THE FORECAST ON FRIDAY NIGHT AND
SATURDAY.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
AS OF 145 AM SATURDAY...
AN EXPANSIVE STORM SYSTEM CENTERED ON THE FL GULF COAST WILL AFFECT
THE SOUTHEAST STATES AND CAROLINAS THROUGHOUT TODAY AND TONIGHT.
CURRENTLY... DESPITE FAIRLY WIDESPREAD LIGHT RAIN... WITH THE
EXCEPTION OF FAY... VFR CONDITIONS DOMINATE WITH MOST VSBYS AOA 6SM
AND CIGS AOA 4 000 FT... WHILE FAY HAS SEEN A BAND OF HEAVIER RAIN
BRINGING IN IFR CIGS AND MVFR VSBYS. THESE IFR CIGS ARE LIKELY TO
CONTINUE TO ADVECT INTO FAY THROUGH 12Z... AND MAY CREEP INTO THE
VICINITY OF RWI. AT INT/GSO/RDU... VFR CIGS AND VSBYS ARE EXPECTED
TO PREVAIL THROUGH 12Z... ALTHOUGH VSBYS MAY BRIEFLY DROP TO MVFR IN
ANY HEAVIER RAIN BANDS. AFTER 12Z... RDU/RWI SHOULD FALL TO MAINLY
MVFR... LASTING UNTIL AROUND 19-21Z... WITH BRIEF IFR CIGS POSSIBLE
BETWEEN 12Z AND 16Z. INT/GSO SHOULD REMAIN VFR... ALTHOUGH A BRIEF
DROP TO MVFR 12Z-16Z THIS MORNING IS POSSIBLE. FAY IS LIKELY TO
EXPERIENCE THE WORST AVIATION CONDITIONS WITH IFR CONDITIONS HOLDING
THROUGH 06Z TONIGHT. AT INT/GSO/RWI/RDU... CIGS ARE EXPECTED TO
IMPROVE TO VFR AFTER 21Z AS DRIER LOW LEVEL AIR NOSES IN FROM HIGH
PRESSURE TO THE NORTH... WITH JUST PATCHY DRIZZLE AT MOST FROM 21Z
THROUGH THE END OF THE TAF VALID PERIOD (06Z SUN).
LOOKING BEYOND 06Z SUN... EXPECT IMPROVEMENT TO MVFR AT FAY 06Z-09Z
THEN TO VFR BY 12Z... AND MAINLY VFR CIGS AT ALL OTHER SITES THROUGH
SUNDAY. EXPECT VFR CONDITIONS TO DOMINATE THROUGH MON NIGHT. PASSAGE
OF A MID LEVEL TROUGH AND SURFACE COLD FRONT FROM THE NW WILL BRING
A RISK OF SUB-VFR CONDITIONS TUE/TUE NIGHT. VFR CONDITIONS RETURN
FOR WED. -GIH
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...SMITH
NEAR TERM...HARTFIELD
SHORT TERM...SMITH
LONG TERM...SMITH
AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
134 AM EDT SAT APR 19 2014
.SYNOPSIS...
LOW PRESSURE OVER NORTH FLORIDA WILL MOVE SLOWLY UP THE SOUTHEAST
COAST THROUGH MONDAY. STIFF NORTHEAST WINDS WILL CONTINUE THROUGH
SUNDAY. WIDESPREAD RAIN WILL BECOME MORE SPORADIC AS THE WEEKEND
PROGRESSES. HIGH PRESSURE WILL THEN REASSERT ITSELF BRIEFLY BEFORE A
COLD FRONT MOVES THROUGH LATE ON TUESDAY. DRY HIGH PRESSURE WILL
RETURN BY THE END OF THE UPCOMING WEEK.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
AS OF 1100 PM FRIDAY...KLTX AS WELL AS MOSAIC RADAR TRENDS ILLUSTRATE
THE RAIN COMPLETELY BLANKETING THE ILM CWA. WIDESPREAD STRATIFORM
LIGHT TO MODERATE RAIN IS NOW FALLING ACROSS THE FA...WITH POCKETS
OF HEAVIER RAIN ACROSS WILLIAMSBURG AND HORRY COUNTIES. THE SFC
COASTAL TROF LIES NE-SW JUST OFFSHORE AND PARALLEL TO THE ILM
COASTAL CWA. THE HEAVIER RAIN ACROSS THE MENTIONED ILM CWA IS
ASSOCIATED WITH CONVECTION THAT WAS SOUTH OF THE COASTAL TROF THAT
PUSHED NORTHWARD ACROSS THIS TROF AND THEN ONSHORE WHERE
INSTABILITY LACKED TO SUSTAIN THE CONVECTION. AS A RESULT...THIS
CONVECTIVE PCPN TRANSITIONED INTO STRATIFORM MODERATE TO POCKETS
OF HEAVY RAIN. WITH ALL THIS SAID...LOOKING AT CATEGORICAL POPS
FOR THE REMAINDER OF THE OVERNIGHT AND INTO THE 1ST HALF OF
SATURDAY.
HIGH TIDE LEVELS TO REMAIN BELOW MINOR COASTAL FLOOD ADVISORY
CRITERIA OVERNIGHT...WITH THE PEAK OCCURRING AROUND MIDNIGHT.
VIA CURRENT RADAR TRENDS AND THE LATEST HRRR OUTPUT...THE ONSHORE
MOVEMENT OF MODERATE TO HEAVY PCPN CURRENTLY BEING EXPERIENCED BY
CHS...WILL TRANSLATE NORTHWARD OVERNIGHT INTO THE ILM CWA. IT IS
PROGGED TO LOSE SOME OF ITS PUNCH AS IT REACHES THE ILM CWA DURING
THIS LATE EVENING THROUGH THE SAT PRE-DAWN HOURS. AS A RESULT...
HAVE REFRAINED FROM ISSUING A COASTAL FLOOD ADVISORY AT THIS TIME
FOR DOWNTOWN ILM AND PORTIONS OF CAPE FEAR SOUTH OF SNOWS CUT
RIDGE. WILL CONTINUE TO MONITOR FOR INCREASING RAINFALL COINCIDING
WITH THE HIGH ASTRONOMICAL TIDES. HOWEVER...LIKE PREVIOUSLY SAID...
LOOKS LIKE THE HEAVIER PCPN TO ARRIVE MUCH LATER THEN THE HIGH TIDE
OCCURRENCE LATE THIS EVENING.
MIN TEMPS TONIGHT LOOK AOK...WITH VERY LITTLE MASSAGING NEEDED TO
THE DOWNSIDE. VIA VARIOUS MODEL TIME HEIGHT DISPLAYS ACROSS THE
FA...A NE-ENE 30 TO 40 KT WIND WILL PERSIST JUST OFF THE DECK
OVERNIGHT THRU SATURDAY. SOME OF THESE WINDS MAY GET CARRIED TO
THE SFC AS WIND GUSTS OR BY FURTHER INCREASING SUSTAINED VALUES.
AS A RESULT...HAVE TWEAKED WINDS UPWARDS ACROSS THE CWA ESPECIALLY
CLOSER TO THE COAST WHERE WINDS ARE PRIMARILY ONSHORE. WITH THE
COASTAL TROF REMAINING OFFSHORE...OVERNIGHT TEMPS WILL HOLD IN THE
50S CLOSER TO THE COAST AND IN THE 40S THE FURTHER INLAND.
PREVIOUS DISCUSSION...........................................
AS OF 300 PM FRIDAY...A CUTOFF LOW WILL DRIFT ACROSS THE GULF COAST
STATES THROUGH THE OVERNIGHT HOURS. THE ASSOCIATED SURFACE LOW WILL
SLOWLY MOVE FROM THE NORTHERN GULF OF MEXICO...ACROSS NORTHERN
FLORIDA TO REACH THE GEORGIA COAST BY 12Z SATURDAY. LOW-LEVEL
CONVERGENCE IN THE VICINITY OF THE SURFACE LOW AND ALONG THE WARM
FRONTAL BOUNDARY JUST OFFSHORE WILL COUPLE WITH MID AND UPPER-LEVEL
DIFFLUENCE AHEAD OF THE CUTOFF LOW TO ENHANCE LIFT ACROSS THE REGION
THROUGH TONIGHT. THE WIDESPREAD RAINFALL CURRENTLY SURGING FROM THE
NORTHERN GULF ACROSS MUCH OF GEORGIA WILL PROGRESS NORTHEAST AND
OVERSPREAD THE CWA THIS EVENING. THE SURFACE TROUGH/FRONTAL BOUNDARY
IS EXPECTED TO REMAIN OFFSHORE OVERNIGHT WHICH WILL RESULT IN
CONTINUED NORTHEAST SURFACE WINDS FOR THE ILM CWA. MOS GUIDANCE IS
IN VERY GOOD AGREEMENT WITH MIN TEMPS TONIGHT. WITH A MIXED BOUNDARY
LAYER...EXPECT LOWS TO RANGE FROM AROUND 50 INLAND TO NEAR 55 ALONG
THE COAST.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/...
AS OF 300 PM FRIDAY...PERIOD WILL LIKELY BEGIN WITH AN ONGOING
WIDESPREAD RAINFALL EVENT ASSOCIATED WITH A LOW PRESSURE CENTER AND
ITS ASSOCIATED FRONTAL SYSTEM OVER THE DEEP SOUTH. SATURDAY MORNING
WILL FIND THE LOW MOVING OFFSHORE NORTHERN FLORIDA AND INTO THE
ATLANTIC WITH A WARM FRONT LINED UP JUST OFFSHORE THE SOUTHEAST US
COAST. THE LOW WILL DRIFT NORTHEAST THROUGH THE SHORT TERM WITH
LITTLE CHANGE IN INTENSITY AS IT WILL BE NEARLY VERTICALLY STACKED
WITH ITS ASSOCIATED UPPER LOW. HAVE AGAIN LEANED ON THE GFS/ECMWF
SOLUTIONS AS THEY SEEMED IN BETTER AGREEMENT THAN THE NAM WHICH GOES
FOR AN OVERALL DRYER FORECAST. DID NOT LIKE HOW THE NAM WEAKENS AND
THEN TRIES TO WASH OUT THE SYSTEM EARLY. PREVIOUS EXPERIENCE SHOWS
THAT THESE TYPES OF SYSTEMS HANG IN LONGER THAN GUIDANCE WOULD
INDICATE.
GIVEN THE ABOVE AND BASED ON MOVEMENT OF SYSTEM WILL START OFF
SATURDAY WITH WIDESPREAD MODERATE STRATIFORM RAIN AND GRADUALLY
TAPERING OFF PRECIPITATION THEREAFTER. CHANCE POPS AND EXTENSIVE
CLOUD COVER WILL EXTEND INTO SUNDAY...WITH CLEARING SKIES SUNDAY
NIGHT AND NO MENTIONABLE POPS AFTER MIDNIGHT.
A COOL NORTHEAST FLOW AND EXTENSIVE CLOUD COVER WILL SUPPRESS
DAYTIME TEMPERATURES...WITH HIGHS RANGING FROM THE UPPER 50S TO
LOWER 60S ON SATURDAY...AND UPPER 60S ON SUNDAY. OVERNIGHT
TEMPERATURES WILL BE ON THE MILD SIDE...MAINLY UPPER 40S TO LOWER
50S BOTH NIGHTS.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
AS OF 300 PM FRIDAY...COOL AND UNSETTLED TO BEGIN THE PERIOD...BUT
WARMER AND MORE TYPICAL MID-SPRING WEATHER EXPECTED TO FOLLOW FOR
THE MIDDLE AND END OF THE UPCOMING WEEK.
A VERY SLOW MOVING CUTOFF LOW AND ITS ASSOCIATED SURFACE
REFLECTION WILL FINALLY BE PUSHING AWAY FROM THE COAST MONDAY AS A
WEAK RIDGE OF HIGH PRESSURE BUILDS SOUTH AND DEFLECTS IT OFFSHORE.
WHILE LOW LEVEL CLOUDINESS MAY PERSIST THE FIRST PART OF
MONDAY...DRYING OF THE COLUMN WILL OCCUR THROUGH THE DAY AND A LOT
OF SUNSHINE IS EXPECTED MONDAY WITH TEMPS JUST BELOW SEASONABLE
NORMS. THIS WILL BE SHORT LIVED HOWEVER...AS A COLD FRONT WORKS
EAST ON TUESDAY...LIKELY CROSSING THE CWA TUESDAY NIGHT. THIS WILL
BE ACCOMPANIED BY GOOD CHANCES FOR SHOWERS AND ISOLATED TSTMS.
AHEAD OF THIS COLD FRONT TEMPS WILL WARM WELL INTO THE 70S...BUT
SOME CAA BEHIND THE BOUNDARY WILL DRIVE TEMPS TO SEASONABLE OR
JUST BELOW AGAIN WED/THU...EVEN WITH AMPLE LATE-APRIL SUNSHINE.
HIGH PRESSURE DRIFTING OFFSHORE BY THE END OF THE WEEK WILL BEGIN
A NICE WARMING TREND BEGINNING ON FRIDAY.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
AS OF 06Z...EXPECT IFR CONDITIONS TO PREVAIL OVERNIGHT AS -RA/RA
CONTINUES TO SPREAD ACROSS THE EASTERN CAROLINAS. THE CONSTANT
RAINFALL SHOULD HELP TO LOWER CIGS BELOW 1KFT AT MOST TERMS.
NORTHEAST WINDS 15 KT WITH GUSTS OVER 20 KT WILL CONTINUE INTO THIS
MORNING. SLOW-MOVING LOW PRESSURE OVER NORTH FLORIDA WILL BRING
RAIN THROUGH MUCH OF THE DAY. FCST SOUNDINGS AND GUIDANCE ARE IN
GOOD AGREEMENT ABOUT IFR STRATUS PERSISTING THROUGH THE MORNING
HOURS. CIGS MAY LIFT TO MVFR IN THE AFTERNOON...BUT THIS LOOKS LIKE
THE BEST CASE SCENARIO. LOOK FOR GUSTY NORTHEAST WINDS 15-25 KT
DURING THE DAY AS A WARM FRONT REMAINS POSITIONED OFFSHORE. MVFR/IFR
CIGS ARE EXPECTED TO REMAIN IN PLACE THROUGH THE END OF THE TAF
PERIOD...EVEN AS THE RAIN TAPERS OFF BY EVENING.
EXTENDED OUTLOOK...MVFR/IFR CIGS WILL LINGER OVERNIGHT SATURDAY INTO
SUNDAY...LOWEST ALONG THE COAST. BECOMING VFR ON MONDAY. CHANCE OF
SHOWERS ON TUESDAY WITH A COLD FRONT. VFR ON WEDNESDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1100 PM FRIDAY...NE-ENE WINDS REMAIN QUITE ACTIVE ACROSS THE
AREA WATERS. A TIGHTENED SFC PG FOR THE REMAINDER OF THE NIGHT AND
CONTINUING INTO SATURDAY...AND THE 40+ KT WINDS JUST OFF THE
DECK...WILL COMBINE TO PRODUCE A NE WIND AT 15-25 KT ACROSS THE
LOCAL WATERS FOR THE REMAINDER OF THE NIGHT AND INTO SATURDAY.
STRONGLY WORDED SCA REMAINS IN PLACE BUT WILL HAVE TO ONCE AGAIN
WATCH FOR FUTURE CONDITIONS THAT MAY REQUIRE GALES. SIGNIFICANT
SEAS WILL HOLD RELATIVELY IN THE 4 TO 7 FOOT RANGE WITH SEAS
APPROACHING 8 TO 9 FT ACROSS THE OUTER WATERS OFF CAPE FEAR...AND
ALSO OFF CAPE ROMAIN. DOMINANT PERIODS WILL RUN 6 TO 7 SECONDS.
PREVIOUS DISCUSSION.................................
AS OF 3:00 PM FRIDAY...SURFACE LOW PRESSURE WILL DRIFT FROM THE
NORTHERN GULF OF MEXICO ACROSS NORTHERN FLORIDA TO THE GEORGIA
COAST BY EARLY SATURDAY. AN ASSOCIATED FRONTAL BOUNDARY WILL
EXTEND NORTHEASTWARD FROM THE LOW CENTER AND WILL APPROACH THE
COASTAL WATERS FROM THE SOUTH OVERNIGHT. AS THE FRONT NEARS THE
WATERS...WINDS WILL VEER TOWARDS THE ENE AND ARE EXPECTED TO
LIGHTEN UP A BIT IN RESPONSE TO A WEAKER GRADIENT. DESPITE THE
POSSIBILITY OF WINDS FALLING BELOW SMALL CRAFT ADVISORY
THRESHOLDS...ROUGH SEAS WILL WARRANT ITS CONTINUATION THROUGHOUT
THE PERIOD.
SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
AS OF 300 PM FRIDAY...SMALL CRAFT ADVISORY WILL EXTEND THROUGH
MOST...IF NOT ALL OF THE NEAR TERM AS A STEADY MODERATE
NORTHEASTERLY FLOW WILL CONTINUE THROUGH THE PERIOD. ALTHOUGH WINDS
EARLY IN THE PERIOD ON SATURDAY MORNING WILL BE MODEST...ONLY IN THE
10 TO 15 KT RANGE...THEY WILL INCREASE TO 20 TO 25 KTS SATURDAY
NIGHT AS A LOW PRESSURE SYSTEM MOVES EAST OF FLORIDA. SEAS WILL
BUILD INTO THE 6 TO 10 FT RANGE AS A RESULT. HAZARDOUS BOATING
CONDITIONS WILL LIKELY EXTEND THROUGH THE ENTIRE WEEKEND.
LONG TERM /MONDAY THROUGH WEDNESDAY/...
AS OF 300 PM FRIDAY...SLOW MOVING LOW PRESSURE OFF THE SOUTHEAST
COAST WILL GRADUALLY SHIFT AWAY FROM THE AREA ON MONDAY...LEAVING
NORTHERLY WINDS WHICH WILL EASE FROM 15-20 KTS EARLY TO LESS THAN 10
KTS MONDAY NIGHT. A RIDGE OF HIGH PRESSURE THEN BUILDS DOWN INTO THE
AREA BRIEFLY AHEAD OF A COLD FRONT WHICH WILL CROSS TUESDAY NIGHT.
WINDS RESPOND QUICKLY TO THESE CHANGING CONDITIONS...BECOMING SW AT
10-20 KTS TUESDAY...AND THEN QUICKLY VEERING TO THE NW BEHIND THE
COLD FRONT TUESDAY NIGHT AT 15-25 KTS. THIS IS WHEN THE HIGHEST SEAS
ARE EXPECTED AS WELL...AND SOME 6 FT SEAS ARE POSSIBLE TUESDAY INTO
WEDNESDAY WHEN A BRIEF SCA MAY BE NEEDED. WINDS THEN REMAIN FROM THE
NW ON WEDNESDAY...BUT WITH SLOWLY DECREASING SPEEDS.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT SUNDAY FOR AMZ250-252-254-
256.
&&
$$
NEAR TERM...DCH/CRM
SHORT TERM...REK
LONG TERM...JDW
AVIATION...BJR/RJD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
115 AM CDT SAT APR 19 2014
.UPDATE...
ISSUED AT 115 AM CDT SAT APR 19 2014
MAIN UPDATES EARLY THIS MORNING WERE TO POPS AND
TEMPERATURES...ADJUSTING BASED ON LATEST OBSERVATIONS...RADAR
IMAGERY...AND NEAR TERM HR MODEL TRENDS.
LINE OF SHOWERS MAINLY NORTHWEST WILL LIFT EAST-NORTHEAST BETWEEN
NOW AND 10-12Z AS A MID LEVEL LOW MOVES THROUGH THE NORTHERN
PLAINS. ANOTHER AREA OF SHOWERS SOUTHEAST NEAR A STRONG LOW LEVEL
JET WILL PERSIST BUT WILL ALSO PUSH FARTHER EAST BY DAWN.
A PERIOD OF STRONG WEST/NORTHWEST WINDS IS ACCOMPANYING THE LINE
OF SHOWERS/CLOUDS ACROSS THE WEST WITH PEAK GUSTS ANYWHERE FROM 30
TO 45KTS. WINDS DIMINISH QUICKLY BEHIND THIS FRONTAL FEATURE.
UPDATE ISSUED AT 956 PM CDT FRI APR 18 2014
WILL GO AHEAD AND LET THE WIND ADVISORY EXPIRE AT 10 PM. ALTHOUGH
NEAR ADVISORY TO LOW ADVISORY CRITERIA WINDS MAY LINGER AROUND
JAMESTOWN AND CARRINGTON TO RUGBY FOR ANOTHER HOUR OR SO.
OTHERWISE UPDATED POPS BASED ON LATEST RADAR IMAGERY AND 01 UTC
HRRR GUIDANCE. PRECIPITATION WILL SPREAD QUICKLY EAST ACROSS THE
AREA WITH MAYBE SOME LINGERING LIGHT PRECIPITATION IN THE FAR EAST
09-12 UTC. WINDS WILL DIMINISH EAST...AND ARE BEGINNING TO SHIFT
WEST IN THE FAR WEST. BREEZY WEST WINDS ON SATURDAY.
UPDATE ISSUED AT 708 PM CDT FRI APR 18 2014
SURFACE LOW PRESSURE NEAR BUFFALO SOUTH DAKOTA WITH STRONG
SOUTHEAST FLOW CONTINUING OVER THE EASTERN HALF OF NORTH DAKOTA.
SCATTERED TO NUMEROUS SHOWERS ARE CURRENTLY MOVING INTO WESTERN
NORTH DAKOTA. EXPECT THESE TO TRANSLATE EAST THROUGH THE EVENING.
HAVE UPDATED POP GRIDS BASED ON LATEST RADAR ANALYSIS. KEEPING
HIGHER POPS OUT OF THE CENTRAL PORTION OF THE STATE UNTIL MID
EVENING.
HAVE ALLOWED THE WIND ADVISORY TO EXPIRE AT MINOT AND BISMARCK.
AND EXTENDED IT THROUGH 10 PM OVER EASTERN PORTIONS OF CENTRAL
NORTH DAKOTA. THE JAMES RIVER VALLEY WAS ALREADY IN THE ADVISORY
THROUGH 10 PM.
UPDATE ISSUED AT 548 PM CDT FRI APR 18 2014
WILL LET THE WIND ADVISORY EXPIRE AT 7 PM OVER THE FAR WEST
PORTION OF THE ADVISORY...INCLUDING BISMARCK AND MINOT.
HOWEVER...LATEST RAP GUIDANCE SUGGESTS THAT STRONG SOUTHERLY
925-850MB WINDS WILL ACTUALLY INCREASE THIS EVENING OVER EASTERN
NORTH DAKOTA INCLUDING THE JAMES RIVER VALLEY INTO THE TURTLE
MOUNTAINS WITH THE MIXING LAYER REMAINING ELEVATED INTO THE MID TO
LATE EVENING HOURS. THE JAMES RIVER VALLEY GOES THROUGH 10 PM BUT
WILL EXTEND THIS NORTH THROUGH THE TURTLE MOUNTAINS AND ADD
ANOTHER LAYER COUNTIES TO THE WEST. OTHERWISE NO SIGNIFICANT
UPDATES AT THIS TIME. WILL SEND PRODUCTS OUT BY 6 PM CDT.
&&
.SHORT TERM...(THIS AFTERNOON THROUGH SATURDAY)
ISSUED AT 250 PM CDT FRI APR 18 2014
LOW PRESSURE OVER EASTERN MONTANA CONTINUES TO TIGHTEN THE
PRESSURE GRADIENT OVER WESTERN AND CENTRAL NORTH DAKOTA. SOLID
WIND ADVISORY CRITERIA IS BEING MET OVER THE ADVISED AREA...SO
WILL CONTINUE WITH THE WIND HEADLINE FOR THIS UPDATE.
RAIN SHOWERS ARE BEGINNING TO INCREASE IN COVERAGE OVER EASTERN
MONTANA THIS AFTERNOON AHEAD OF AN APPROACHING SHORTWAVE. THIS
ACTIVITY IS EXPECTED TO ENTER WESTERN AND CENTRAL NORTH DAKOTA
LATER THIS AFTERNOON AND TONIGHT. LAPSE RATES ALOFT DO NOT APPEAR
CONDUCIVE FOR THUNDERSTORM DEVELOP SOUTH LATER THIS AFTERNOON AND
EVENING. THEREFORE...REMOVED THUNDER WORDING FROM THE APPROPRIATE
ZONES IN THE FIRST PERIOD.
THE MAIN FORECAST CHALLENGE WILL BE DETERMINING THE GREATEST
POTENTIAL FOR RAIN SHOWERS TONIGHT. THE GFS/GEM/NAM KEEP THE
HIGHEST PRECIP CHANCES ALONG THE INTERNATIONAL BOUNDARY (PROXIMATE
TO THE MAIN UPPER LEVEL SHORTWAVE ENERGY) WHEREAS THE ECMWF HAS
HIGH PRECIP CHANCES OVER CENTRAL NORTH DAKOTA TONIGHT. FOR NOW
WILL FOLLOW A BLENDED APPROACH AND KEEP THE HIGHEST POPS NORTH AND
EXTEND THEM SOUTH INTO CENTRAL NORTH DAKOTA THIS EVENING.
AS THE SHORTWAVE MOVES THROUGH THE AREA...DRY WESTERLY FLOW WILL
DEVELOP WITH PRECIPITATION CHANCES ENDING FROM WEST TO EAST AFTER
MIDNIGHT.
DRY WESTERLY FLOW WILL CONTINUE SATURDAY WITH HIGHS EXPECTED TO
INCREASE INTO THE 60S. THERE COULD BE SOME FIRE WEATHER ISSUES
SATURDAY. SEE FIRE WEATHER DISCUSSION BELOW.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 250 PM CDT FRI APR 18 2014
THE HIGHLIGHTS OF THE EXTENDED FORECAST ARE A MILD EASTER FOLLOWED
BY A POTENTIAL SIGNIFICANT STORM SYSTEM TUESDAY NIGHT THROUGH
THURSDAY NIGHT.
WIDESPREAD HIGHS IN THE 60S TO LOWER 70S ARE FORECAST ACROSS
WESTERN AND CENTRAL NORTH DAKOTA EASTER SUNDAY IN THE WARM SECTOR
OF A WEAK SURFACE LOW ACROSS NORTHERN NORTH DAKOTA. ISOLATED TO
SCATTERED SHOWERS AND THUNDERSTORMS ARE POSSIBLE DURING THE
AFTERNOON WITH THE APPROACH OF AN UPPER LEVEL SHORTWAVE AND
SURFACE COLD FRONT. OVERALL INSTABILITY AND MOISTURE IS
LIMITED...THUS NOT EXPECTING A WASHOUT.
LOOKING AHEAD...THE 12 UTC GUIDANCE SUITE CONTINUES TO DEPICT A
SIGNIFICANT TROUGH COMING ONSHORE TO THE PACIFIC COAST
TUESDAY...PLACING THE NORTHERN PLAINS UNDER SOUTHWEST FLOW ALOFT
TUESDAY NIGHT INTO WEDNESDAY. WITH A STRONG LOW LEVEL JET POSSIBLE
TUESDAY NIGHT...AND CONTINUED LOW LEVEL WARM AIR ADVECTION AHEAD
OF THE SURFACE REFLECTION OF THE LOW INTO WEDNESDAY...THE CHANCE
FOR THUNDERSTORMS REMAINS. AT THIS TIME...SEVERE CONVECTION IS
NOT ANTICIPATED. FOR THE 12 UTC RUN TODAY...THE GFS AND ECMWF ARE
IN AGREEMENT ON CLOSING OFF AND PROPAGATING A STRONG UPPER LEVEL
LOW INTO THE NORTHERN PLAINS WEDNESDAY NIGHT INTO THURSDAY. THIS
WOULD SUGGEST THE POTENTIAL FOR ACCUMULATING SNOW THURSDAY NIGHT
INTO FRIDAY ON THE BACKSIDE OF THIS SYSTEM. UNCERTAINTY IN
PRECIPITATION TYPES...AMOUNTS AND PLACEMENT WILL LIKELY REMAIN
INTO EARLY NEXT WEEK. HOWEVER...SIGNIFICANT QPF IS POSSIBLE AND
HYDROLOGIC IMPACTS WILL HAVE TO BE MONITORED.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 115 AM CDT SAT APR 19 2014
LOW PRESSURE WILL MOVE ACROSS WESTERN AND CENTRAL NORTH DAKOTA
TONIGHT. WILL MAINTAIN VFR CEILINGS AND VISIBILITIES THROUGH THE
PERIOD WITH LOWEST CEILINGS AROUND 5K FT AGL AND LOWEST
VISIBILITIES ABOVE 6SM EARLY THIS MORNING. A FRONTAL BOUNDARY WILL
MOVE WEST TO EAST NOW THROUGH 12Z WITH A BRIEF PERIOD OF GUSTY
WINDS. AHEAD OF THIS BOUNDARY...AREAS OF FOG WITH VIS NEAR MVFR
POSSIBLE...BUT SHOULD BE SHORT LIVED. MAINLY CLEAR CONDITIONS
AFTER 12Z. WINDS WILL BE ON THE INCREASE OUT OF THE WEST SATURDAY
SUSTAINED NEAR 20KT WITH GUSTS 25-30KTS THROUGH THE AFTERNOON.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...NH
SHORT TERM...TM
LONG TERM...AYD
AVIATION...NH
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
107 PM EDT SAT APR 19 2014
.SYNOPSIS...
A CANADIAN HIGH PRESSURE SYSTEM WILL MOVE SOUTHEAST ACROSS THE GREAT
LAKES THIS WEEKEND...THEN MOVE OFF THE NEW ENGLAND COAST SUNDAY
NIGHT. THIS WILL ALLOW A LOW PRESSURE SYSTEM TO MOVE ACROSS THE
LOWER GREAT LAKES MONDAY NIGHT...DRAGGING ANOTHER COLD FRONT
ACROSS THE AREA.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
A RIDGE CONTINUES OVER THE LAKE WITH PLENTY OF DRY AIR AND
SUBSIDENCE FOR THE REST OF THE AFTERNOON. SUNNY WILL HANDLE IT.
MADE SOME ADJUSTMENTS TO THE HIGHS...LOWERED THEM A LITTLE BASED
ON THE NOON METARS AND THE HRRR TEMPERATURE FORECAST GUIDANCE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/...
THE CANADIAN HIGH PRESSURE SYSTEM WILL BE THE DOMINANT FEATURE
THROUGH MONDAY. THIS WILL PRODUCE DRY WEATHER THROUGH THE PERIOD
WITH A GRADUAL WARM UP AS THE HIGH SHIFTS EAST AND THE FLOW TURN TO
THE SOUTH. ABOVE NORMAL TEMPS EXPECTED FOR EASTER. FOR SUNDAY THE
NAM CONTINUES TO BE WARMER THAN THE GFS AND THE ECMWF. LEANED
TOWARD THE WARMER NAM...BUT CUT TEMPS A DEGREE OR TWO. THE WARM UP
WILL BE SHORT LIVED HOWEVER. MODELS ARE COMING INTO MUCH BETTER
AGREEMENT ON THE TIMING OF THE NEXT SYSTEM. MODELS CONTINUE TO
MOVE A LOW PRESSURE SYSTEM ACROSS THE LOWER LAKES MONDAY
NIGHT...DRAGGING ANOTHER COLD FRONT ACROSS THE AREA. THE GFS IS
SLIGHTLY FASTER THAN THE NAM AND THE ECMWF SO FOR NOW WILL JUST GO
LIKELY POPS ACROSS THE ENTIRE AREA MONDAY NIGHT. EXPECT SOME
LINGERING SHOWERS IN THE EAST ON TUESDAY.
&&
.LONG TERM /WEDNESDAY THROUGH FRIDAY/...
ALL OF THE MODELS BRING A TRAILING SHORT WAVE INTO THE LONG WAVE
TROUGH EARLY WEDNESDAY. WITH THE HIGH PRESSURE STILL TO THE WEST
THERE IS A DECENT CHANCE FOR A FEW MORE SHOWERS...MAINLY ACROSS NE
OH/NW PA. TEMPERATURES ARE TRICKY...IF IT WERE TO STAY CLOUDY AND
SHOWERY ALL DAY THEN IT COULD BE CHILLY. CONSIDERED MENTIONING SNOW
SHOWERS IN THE FORECAST SINCE THE 850 MB TEMP IS PROGGED TO DROP TO
-4C BUT THE BOUNDARY LAYER WILL PROBABLY STAY WARM ENOUGH FOR RAIN
SHOWERS.
HIGH PRESSURE WILL BUILD ACROSS THE AREA WEDNESDAY NIGHT BUT
RELATIVELY STRONG WARM ADVECTION WILL BE UNDERWAY ACROSS THE UPPER
MIDWEST. SOME WARM ADVECTION CLOUDS WILL SPREAD ACROSS THE AREA BY
THURSDAY MORNING AND CANNOT RULE OUT A SHOWER ALTHOUGH THE ODDS
WOULD FAVOR A DRY DAY WITH MODERATING TEMPERATURES.
NOT A LOT OF CONFIDENCE ON THE TIMING OF THE NEXT FRONT YET...
PROBABLY SOME TIME ON FRIDAY. THERE COULD BE TWO FRONTS OR A
PREFRONTAL TROUGH. WILL HAVE A CHANCE OF SHOWERS AND WILL KEEP THE
TEMPERATURES MILD ON FRIDAY SINCE IT APPEARS THE COLDER AIR WILL
HANG BACK AND NOT ARRIVE UNTIL FRIDAY NIGHT.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
VFR TO THE MAX OVER THE NEXT 36 HOURS AS SURFACE AND MID LEVEL
HIGH PRESSURE DOMINATES THE REGION. ONLY EXPECTING SOME CIRRUS
CLOUDS SPILLING NORTH INTO AKRON CANTON AND YOUNGSTOWN THIS
AFTERNOON AND EVENING. MORE CIRRUS WILL SCOOT IN FROM THE WEST AT
TOLEDO AND FINDLAY AS WELL. OTHERWISE...WINDS SHOULD BE FROM THE
NORTH TO NORTHEAST AT 10 KNOTS DIMINISHING TO 5 TO 10 KNOTS TONIGHT.
.OUTLOOK...NON VFR IS POSSIBLE MONDAY NIGHT INTO EARLY TUESDAY.
&&
.MARINE...
ALLOWED THE SMALL CRAFT ADVISORY TO EXPIRE. THE WINDS AND WAVES
WERE DECREASING. CONDITIONS WILL STILL BE A LITTLE CHOPPY.
HIGH PRESSURE WILL BUILD OVER THE LAKE BY THIS EVENING AND THE WIND
WILL DIMINISH QUICKLY. WINDS WILL VEER MORE FROM THE SOUTHEAST
TONIGHT ITO SUNDAY. THE GRADIENT WILL BE WEAK ENOUGH SUNDAY FOR A
LAKE BREEZE IN MOST AREAS. THE SOUTH GRADIENT WILL BE STRONGER BY
SUNDAY NIGHT INTO MONDAY AHEAD OF THE NEXT COLD FRONT BUT THE WIND
AND WAVES WILL LIKELY NOT PICK UP ON THE LAKE UNTIL AFTER THE COLD
FRONTAL PASSAGE EARLY TUESDAY.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...DJB
NEAR TERM...KIELTYKA
SHORT TERM...DJB
LONG TERM...KOSARIK
AVIATION...LOMBARDY
MARINE...KOSARIK/LOMBARDY
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
1242 PM EDT SAT APR 19 2014
.SYNOPSIS...
A CANADIAN HIGH PRESSURE SYSTEM WILL MOVE SOUTHEAST ACROSS THE GREAT
LAKES THIS WEEKEND...THEN MOVE OFF THE NEW ENGLAND COAST SUNDAY
NIGHT. THIS WILL ALLOW A LOW PRESSURE SYSTEM TO MOVE ACROSS THE
LOWER GREAT LAKES MONDAY NIGHT...DRAGGING ANOTHER COLD FRONT
ACROSS THE AREA.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
A RIDGE CONTINUES OVER THE LAKE WITH PLENTY OF DRY AIR AND
SUBSIDENCE FOR THE REST OF THE AFTERNOON. SUNNY WILL HANDLE IT.
MADE SOME ADJUSTMENTS TO THE HIGHS...LOWERED THEM A LITTLE BASED
ON THE NOON MTR`S AND THE HRRR TEMPERATURE FORECAST GUIDANCE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/...
THE CANADIAN HIGH PRESSURE SYSTEM WILL BE THE DOMINANT FEATURE
THROUGH MONDAY. THIS WILL PRODUCE DRY WEATHER THROUGH THE PERIOD
WITH A GRADUAL WARM UP AS THE HIGH SHIFTS EAST AND THE FLOW TURN TO
THE SOUTH. ABOVE NORMAL TEMPS EXPECTED FOR EASTER. FOR SUNDAY THE
NAM CONTINUES TO BE WARMER THAN THE GFS AND THE ECMWF. LEANED
TOWARD THE WARMER NAM...BUT CUT TEMPS A DEGREE OR TWO. THE WARM UP
WILL BE SHORT LIVED HOWEVER. MODELS ARE COMING INTO MUCH BETTER
AGREEMENT ON THE TIMING OF THE NEXT SYSTEM. MODELS CONTINUE TO
MOVE A LOW PRESSURE SYSTEM ACROSS THE LOWER LAKES MONDAY
NIGHT...DRAGGING ANOTHER COLD FRONT ACROSS THE AREA. THE GFS IS
SLIGHTLY FASTER THAN THE NAM AND THE ECMWF SO FOR NOW WILL JUST GO
LIKELY POPS ACROSS THE ENTIRE AREA MONDAY NIGHT. EXPECT SOME
LINGERING SHOWERS IN THE EAST ON TUESDAY.
&&
.LONG TERM /WEDNESDAY THROUGH FRIDAY/...
ALL OF THE MODELS BRING A TRAILING SHORT WAVE INTO THE LONG WAVE
TROUGH EARLY WEDNESDAY. WITH THE HIGH PRESSURE STILL TO THE WEST
THERE IS A DECENT CHANCE FOR A FEW MORE SHOWERS...MAINLY ACROSS NE
OH/NW PA. TEMPERATURES ARE TRICKY...IF IT WERE TO STAY CLOUDY AND
SHOWERY ALL DAY THEN IT COULD BE CHILLY. CONSIDERED MENTIONING SNOW
SHOWERS IN THE FORECAST SINCE THE 850 MB TEMP IS PROGGED TO DROP TO
-4C BUT THE BOUNDARY LAYER WILL PROBABLY STAY WARM ENOUGH FOR RAIN
SHOWERS.
HIGH PRESSURE WILL BUILD ACROSS THE AREA WEDNESDAY NIGHT BUT
RELATIVELY STRONG WARM ADVECTION WILL BE UNDERWAY ACROSS THE UPPER
MIDWEST. SOME WARM ADVECTION CLOUDS WILL SPREAD ACROSS THE AREA BY
THURSDAY MORNING AND CANNOT RULE OUT A SHOWER ALTHOUGH THE ODDS
WOULD FAVOR A DRY DAY WITH MODERATING TEMPERATURES.
NOT A LOT OF CONFIDENCE ON THE TIMING OF THE NEXT FRONT YET...
PROBABLY SOME TIME ON FRIDAY. THERE COULD BE TWO FRONTS OR A
PREFRONTAL TROUGH. WILL HAVE A CHANCE OF SHOWERS AND WILL KEEP THE
TEMPERATURES MILD ON FRIDAY SINCE IT APPEARS THE COLDER AIR WILL
HANG BACK AND NOT ARRIVE UNTIL FRIDAY NIGHT.
&&
.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
SUBSIDENCE SHOULD INCREASE THIS MORNING AS HIGH PRESSURE BUILDS IN
FROM THE NORTH. VFR WITH A FEW PATCHES OF STRATOCUMULUS THIS
MORNING THEN PATCHY HIGH CLOUDS. THE EAST TO NORTHEAST WIND WILL
BE A BIT GUSTY AT TIMES TODAY. VFR CONTINUES INTO SUNDAY.
.OUTLOOK...NON VFR IS POSSIBLE MONDAY NIGHT INTO TUESDAY.
&&
.MARINE...
ALLOWED THE SMALL CRAFT ADVISORY TO EXPIRE. THE WINDS AND WAVES
WERE DECREASING. CONDITIONS WILL STILL BE A LITTLE CHOPPY.
HIGH PRESSURE WILL BUILD OVER THE LAKE BY THIS EVENING AND THE WIND
WILL DIMINISH QUICKLY. WINDS WILL VEER MORE FROM THE SOUTHEAST
TONIGHT ITO SUNDAY. THE GRADIENT WILL BE WEAK ENOUGH SUNDAY FOR A
LAKE BREEZE IN MOST AREAS. THE SOUTH GRADIENT WILL BE STRONGER BY
SUNDAY NIGHT INTO MONDAY AHEAD OF THE NEXT COLD FRONT BUT THE WIND
AND WAVES WILL LIKELY NOT PICK UP ON THE LAKE UNTIL AFTER THE COLD
FRONTAL PASSAGE EARLY TUESDAY.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...DJB
NEAR TERM...KIELTYKA
SHORT TERM...DJB
LONG TERM...KOSARIK
AVIATION...KOSARIK
MARINE...KOSARIK/LOMBARDY
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
1043 PM EDT SUN APR 20 2014
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN ACROSS THE AREA BEFORE A COLD FRONT
CROSSES EAST ON TUESDAY. DRY HIGH PRESSURE BUILDS BACK IN WEDNESDAY
AND THURSDAY WITH ANOTHER COLD FRONT AFFECTING THE REGION ON FRIDAY.
&&
.NEAR TERM /THROUGH MONDAY/...
AS OF 1030 PM...NC PIEDMONT STRATOCU HAS BEEN STEADILY OOZING AWAY
FROM THE FORECAST AREA THIS EVENING...SO THE SKY COVER FORECAST HAS
BEEN LOWERED ACROSS OUR SOUTHEAST TIER OF ZONES. OTHERWISE...
PRIMARILY THIN CIRRUS WILL PASS OVER THE REGION THROUGH THE
OVERNIGHT...BUT THIS IS NOT EXPECTED TO HAVE A MAJOR IMPACT ON THE
NOCTURNAL COOLING CYCLE. WITH LIGHT MIXING EXPECTED IN THE PIEDMONT
TONIGHT...MIN TEMPS ARE EXPECTED TO AVERAGE JUST A LITTLE BELOW
NORMAL...WHILE SHELTERED MTN VALLEYS WILL AVERAGE AT LEAST 5 DEGREES
BELOW CLIMO. IN FACT...IT APPEARS PATCHY FROST IS LIKELY IN
SHELTERED AREAS OF THE SRN/CTRL MTNS MONDAY MORNING...AND WE HAVE
ADDED THIS TO THE FORECAST. IN ADDITION...VALLEY FOG LOOKS LIKE A
DECENT BET...PRIMARILY IN THE LITTLE TENN BASIN AND ADJACENT
DRAINAGES.
AS OF 750 PM SUNDAY...OTHER THAN PATCHY STRATOCU ACROSS THE EXTREME
SE TIER OF ZONES...SKIES ARE CLEAR ACROSS THE AREA AT MID-EVENING.
MODEL SOLUTIONS ARE QUITE DISPARATE REGARDING THE EVOLUTION OF THIS
STRATOCU LAYER OVERNIGHT...WITH THE NAM BEING SOMEWHAT OF AN OUTLIER
IN DRAGGING IT WEST TO ENCOMPASS MUCH OF THE NC PIEDMONT/EASTERN SC
PIEDMONT LATER THIS EVENING. IN LIGHT OF THIS...HAVE OPTED TO
INTRODUCE SKY COVER AT THE MOSTLY CLEAR/PARTLY CLOUDY END OF THE
SPECTRUM ACROSS THE EASTERN THIRD OF THE AREA.
AS OF 150 PM EDT SUNDAY...WITH THE UPPER LOW SLOWLY MOVING OUT TO
SEA...ONLY THE FAR EASTERN ZONES SHOULD SEE ANY CLOUD COVER THIS
EVENING. THE NAM IS QUITE AGGRESSIVE IN BRINGING CLOUDS INTO THE WRN
NC PIEDMONT...BUT AS THE GFS AND RUC DO NOT DO THIS...I/VE GONE WITH
A SKY FORECAST CLOSER TO THE DRIER MODELS. THERE SHOULD BE MORE
LOCALLY DENSE FOG IN THE SOUTHWEST IN MTN VALLEYS OVERNIGHT. DRY AIR
AND WEAK MIXING SHOULD KEEP MOST OTHER LOCATIONS ACROSS THE FA FROM
SEEING ANY FOG OVERNIGHT. MIN TEMPS WILL BE COOL...BUT THEY SHOULD
BE WARM ENOUGH TO PREVENT FROST OVER ALL BUT SOME OF THE INTERIOR
NORTHERN MOUNTAIN VALLEYS. MONDAY WILL BE SEASONABLY MILD WITH
INCREASING HIGH CLOUDS DURING THE AFTERNOON HOURS.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
AS OF MIDDAY SUNDAY...UPPER PATTERN BEGINS TO AMPLIFY ACRS THE ERN
CONUS MON NIGHT AS DEEP RIDGE PUSHES INTO THE GREAT PLAINS. CORE OF
TROUGH BEGINS TO DIG ACRS THE GREAT LAKES...AND SFC LOW SUBSEQUENTLY
DEVELOPS AND MOVES INTO NEW ENGLAND DURING THE DAY TUE. THE TRAILING
COLD FRONT IS STILL PROGGED TO ENTER OUR CWFA AT THAT TIME...MOVING
OUT TUE EVENING. WE WILL BE WELL SOUTH OF THE BETTER FORCING THOUGH
SOME DPVA IS PROGGED AS THE AXIS OF THE BROAD TROUGH PASSES.
FRONTOGENESIS AND LLVL CONVERGENCE FIELDS ARE MURKY...SO PRECIP
CHANCES MOSTLY RESULT FROM DECENT PRE-FRONTAL INSTABILITY. CAPE
PROFILES ARE SKINNY ON PROG SOUNDINGS AND DEEP SATURATION IS
INITIALLY EVIDENT. SHEAR PARAMETERS CONTINUE TO PROMPT LITTLE
CONCERN...BUT IN THE WAKE OF THE UPPER TROUGH DRYING RAPIDLY OCCURS
ABV 700 MB. THIS OCCURS IN THE MID TO LATE AFTN WHEN SOME SFC BASED
INSTABILITY IS STILL PRESENT. THUS SOME OF THE LATER STORM ACTIVITY
COULD POSE A MICROBURST AND DAMAGING WIND THREAT...MAINLY OVER THE
PIEDMONT. TEMPS MON NIGHT AND TUE WILL BE A CATEGORY OR TWO ABOVE
NORMAL.
DEEP LAYER DRYING CONTINUES TUE NIGHT AS PLAINS RIDGE MOVES INTO THE
ERN US...AND SKIES WILL CLEAR OVERNIGHT...PERHAPS MORE SLOWLY IN THE
MTNS WHERE A VERY SHALLOW SFC BASED MOIST LAYER REMAINS IN NW FLOW.
BRISK WINDS ARE LIKELY IN THE HIGH ELEVATIONS AT THAT TIME BUT THESE
SUBSIDE TOWARD DAWN WED. DRY AND MOSTLY CLEAR CONDITIONS PERSIST THRU
WED WITH SUBSIDENCE INVERSION ACRS THE FA BUT LACKING MOISTURE
ANYWAY. THICKNESSES DO DROP A BIT FOR WED...RETURNING TEMPS TO AROUND
NORMAL DESPITE PRIME INSOLATION.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
AS OF 230 PM EDT SUNDAY...THE EXTENDED RANGE PERIOD INITIALIZES ON
WEDNESDAY EVENING AS DEEP LAYER RIDGING PREVAILS ACROSS THE
SOUTHEAST. A SURFACE HIGH DIVING OUT OF ONTARIO WILL QUICKLY
TRANSITION TO A BERMUDA TYPE HIGH BY THURSDAY AFTERNOON SETTING UP
RETURN FLOW. MEANWHILE...A NORTHERN STREAM LOW AMPLITUDE UPPER TROF
WILL PUSH THROUGH THE NORTHERN PLAINS WITH SURFACE CYCLOGENESIS
OCCURRING OVER THE CENTRAL PLAINS. A COLD FRONT WILL PUSH
THROUGH THE MISSISSIPPI RIVER VALLEY ON THURSDAY EVENING AS THE
PARENT SURFACE CYCLONE EJECTS NORTHEAST INTO THE GREAT LAKES REGION.
ABOVE MENTIONED HIGH PRESSURE WILL PREVAIL ACROSS THE SOUTHERN
APPALACHIANS...AHEAD OF THE APPROACHING FRONT ON FRIDAY
MORNING/AFTERNOON. A WARM FRONT WILL SURGE NORTHWARD FROM THE GULF
AND WESTERN ATLANTIC SOURCE REGIONS ALLOWING FOR INCREASING
DEWPOINTS AND STEEPENING LAPSE RATES DURING THE AFTERNOON HOURS.
THIS WILL LEAD TO MODEST INSTABILITY ACROSS THE CWFA WITH GFS/ECMWF
SOLUTIONS INDICATIVE OF SBCAPE IN EXCESS OF 1000J/KG WITH ENOUGH
SHEAR TO SUPPORT SOME ORGANIZED CONVECTION. STILL TOO MUCH
UNCERTAINTY TO DIAL IN ON STORM MODES AND SPECIFIC TIMING/INTENSITY.
HOWEVER...CURRENT FCST SOUNDINGS DO INDICATE PW VALUES APPROACHING
1.5 INCHES LEADING TO MODERATELY HEAVY RAIN RATES WITH CAPE PROFILES
SUPPORTIVE OF LARGE HAIL. DUE TO UNCERTAINTY...CAPPED POPS AT HIGH
END CHANCE LEVELS ACROSS THE REGION FOR FRIDAY. THE FRONT WILL PASS
INTO THE COASTAL PLAINS/MIDLANDS BY EARLY MORNING SATURDAY LEADING
TO A DRY FCST UNTIL SUNDAY AFTERNOON. AT THAT TIME POPS SLOWLY RAMP
UP ACROSS THE WESTERNMOST ZONES AS ANOTHER SYSTEM MOVES THROUGH THE
MID-SOUTH AND INTO THE TENNESSEE VALLEY. TEMPERATURES THROUGH THE
EXTENDED RANGE PERIOD WILL REMAIN AT OR JUST ABOVE NORMAL LEVELS
DESPITE THE FROPA FRIDAY EVENING.
&&
.AVIATION /03Z MONDAY THROUGH FRIDAY/...
AT KCLT...VFR STRATOCU AT AROUND 060 WILL LINGER NEAR THE AIRFIELD
THIS EVENING...GENERALLY REMAINING FEW/SCT...ALTHOUGH AN OCCL PERIOD
OF BKN IS POSSIBLE. OTHERWISE...NE WINDS WILL GRADUALLY DIMINISH
OVERNIGHT...BUT ARE EXPECTED TO REMAIN AT AROUND 5 KTS THROUGH AT
LEAST THE MORNING HOURS...BEFORE POSSIBLY VEERING TOWARD THE SE BY
THE END OF MONDAY.
ELSEWHERE...VFR CONDITIONS THROUGH THE PERIOD...WITH GRADUALLY
DIMINISHING NE WINDS EXPECTED. LIGHT/VARIABLE WINDS ARE EXPECTED IN
MANY AREAS MONDAY MORNING...BUT MAY BECOME LIGHT SE BY THE END OF
THE PERIOD.
OUTLOOK...A FAIRLY WET FRONTAL SYSTEM...WITH PIEDMONT
THUNDERSTORMS...IS EXPECTED ON TUE...WITH DRYING RETURNING MID WEEK.
CONFIDENCE TABLE...
02-08Z 08-14Z 14-20Z 20-02Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...SBK
NEAR TERM...JDL/MCAVOY
SHORT TERM...WIMBERLEY
LONG TERM...CDG
AVIATION...JDL
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
758 PM EDT SUN APR 20 2014
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN ACROSS THE AREA BEFORE A COLD FRONT
CROSSES EAST ON TUESDAY. DRY HIGH PRESSURE BUILDS BACK IN WEDNESDAY
AND THURSDAY WITH ANOTHER COLD FRONT AFFECTING THE REGION ON FRIDAY.
&&
.NEAR TERM /THROUGH MONDAY/...
AS OF 750 PM SUNDAY...OTHER THAN PATCHY STRATOCU ACROSS THE EXTREME
SE TIER OF ZONES...SKIES ARE CLEAR ACROSS THE AREA AT MID-EVENING.
MODEL SOLUTIONS ARE QUITE DISPARATE REGARDING THE EVOLUTION OF THIS
STRATOCU LAYER OVERNIGHT...WITH THE NAM BEING SOMEWHAT OF AN OUTLIER
IN DRAGGING IT WEST TO ENCOMPASS MUCH OF THE NC PIEDMONT/EASTERN SC
PIEDMONT LATER THIS EVENING. IN LIGHT OF THIS...HAVE OPTED TO
INTRODUCE SKY COVER AT THE MOSTLY CLEAR/PARTLY CLOUDY END OF THE
SPECTRUM ACROSS THE EASTERN THIRD OF THE AREA.
AS OF 150 PM EDT SUNDAY...WITH THE UPPER LOW SLOWLY MOVING OUT TO
SEA...ONLY THE FAR EASTERN ZONES SHOULD SEE ANY CLOUD COVER THIS
EVENING. THE NAM IS QUITE AGGRESSIVE IN BRINGING CLOUDS INTO THE WRN
NC PIEDMONT...BUT AS THE GFS AND RUC DO NOT DO THIS...I/VE GONE WITH
A SKY FORECAST CLOSER TO THE DRIER MODELS. THERE SHOULD BE MORE
LOCALLY DENSE FOG IN THE SOUTHWEST IN MTN VALLEYS OVERNIGHT. DRY AIR
AND WEAK MIXING SHOULD KEEP MOST OTHER LOCATIONS ACROSS THE FA FROM
SEEING ANY FOG OVERNIGHT. MIN TEMPS WILL BE COOL...BUT THEY SHOULD
BE WARM ENOUGH TO PREVENT FROST OVER ALL BUT SOME OF THE INTERIOR
NORTHERN MOUNTAIN VALLEYS. MONDAY WILL BE SEASONABLY MILD WITH
INCREASING HIGH CLOUDS DURING THE AFTERNOON HOURS.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
AS OF MIDDAY SUNDAY...UPPER PATTERN BEGINS TO AMPLIFY ACRS THE ERN
CONUS MON NIGHT AS DEEP RIDGE PUSHES INTO THE GREAT PLAINS. CORE OF
TROUGH BEGINS TO DIG ACRS THE GREAT LAKES...AND SFC LOW SUBSEQUENTLY
DEVELOPS AND MOVES INTO NEW ENGLAND DURING THE DAY TUE. THE TRAILING
COLD FRONT IS STILL PROGGED TO ENTER OUR CWFA AT THAT TIME...MOVING
OUT TUE EVENING. WE WILL BE WELL SOUTH OF THE BETTER FORCING THOUGH
SOME DPVA IS PROGGED AS THE AXIS OF THE BROAD TROUGH PASSES.
FRONTOGENESIS AND LLVL CONVERGENCE FIELDS ARE MURKY...SO PRECIP
CHANCES MOSTLY RESULT FROM DECENT PRE-FRONTAL INSTABILITY. CAPE
PROFILES ARE SKINNY ON PROG SOUNDINGS AND DEEP SATURATION IS
INITIALLY EVIDENT. SHEAR PARAMETERS CONTINUE TO PROMPT LITTLE
CONCERN...BUT IN THE WAKE OF THE UPPER TROUGH DRYING RAPIDLY OCCURS
ABV 700 MB. THIS OCCURS IN THE MID TO LATE AFTN WHEN SOME SFC BASED
INSTABILITY IS STILL PRESENT. THUS SOME OF THE LATER STORM ACTIVITY
COULD POSE A MICROBURST AND DAMAGING WIND THREAT...MAINLY OVER THE
PIEDMONT. TEMPS MON NIGHT AND TUE WILL BE A CATEGORY OR TWO ABOVE
NORMAL.
DEEP LAYER DRYING CONTINUES TUE NIGHT AS PLAINS RIDGE MOVES INTO THE
ERN US...AND SKIES WILL CLEAR OVERNIGHT...PERHAPS MORE SLOWLY IN THE
MTNS WHERE A VERY SHALLOW SFC BASED MOIST LAYER REMAINS IN NW FLOW.
BRISK WINDS ARE LIKELY IN THE HIGH ELEVATIONS AT THAT TIME BUT THESE
SUBSIDE TOWARD DAWN WED. DRY AND MOSTLY CLEAR CONDITIONS PERSIST THRU
WED WITH SUBSIDENCE INVERSION ACRS THE FA BUT LACKING MOISTURE
ANYWAY. THICKNESSES DO DROP A BIT FOR WED...RETURNING TEMPS TO AROUND
NORMAL DESPITE PRIME INSOLATION.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
AS OF 230 PM EDT SUNDAY...THE EXTENDED RANGE PERIOD INITIALIZES ON
WEDNESDAY EVENING AS DEEP LAYER RIDGING PREVAILS ACROSS THE
SOUTHEAST. A SURFACE HIGH DIVING OUT OF ONTARIO WILL QUICKLY
TRANSITION TO A BERMUDA TYPE HIGH BY THURSDAY AFTERNOON SETTING UP
RETURN FLOW. MEANWHILE...A NORTHERN STREAM LOW AMPLITUDE UPPER TROF
WILL PUSH THROUGH THE NORTHERN PLAINS WITH SURFACE CYCLOGENESIS
OCCURRING OVER THE CENTRAL PLAINS. A COLD FRONT WILL PUSH
THROUGH THE MISSISSIPPI RIVER VALLEY ON THURSDAY EVENING AS THE
PARENT SURFACE CYCLONE EJECTS NORTHEAST INTO THE GREAT LAKES REGION.
ABOVE MENTIONED HIGH PRESSURE WILL PREVAIL ACROSS THE SOUTHERN
APPALACHIANS...AHEAD OF THE APPROACHING FRONT ON FRIDAY
MORNING/AFTERNOON. A WARM FRONT WILL SURGE NORTHWARD FROM THE GULF
AND WESTERN ATLANTIC SOURCE REGIONS ALLOWING FOR INCREASING
DEWPOINTS AND STEEPENING LAPSE RATES DURING THE AFTERNOON HOURS.
THIS WILL LEAD TO MODEST INSTABILITY ACROSS THE CWFA WITH GFS/ECMWF
SOLUTIONS INDICATIVE OF SBCAPE IN EXCESS OF 1000J/KG WITH ENOUGH
SHEAR TO SUPPORT SOME ORGANIZED CONVECTION. STILL TOO MUCH
UNCERTAINTY TO DIAL IN ON STORM MODES AND SPECIFIC TIMING/INTENSITY.
HOWEVER...CURRENT FCST SOUNDINGS DO INDICATE PW VALUES APPROACHING
1.5 INCHES LEADING TO MODERATELY HEAVY RAIN RATES WITH CAPE PROFILES
SUPPORTIVE OF LARGE HAIL. DUE TO UNCERTAINTY...CAPPED POPS AT HIGH
END CHANCE LEVELS ACROSS THE REGION FOR FRIDAY. THE FRONT WILL PASS
INTO THE COASTAL PLAINS/MIDLANDS BY EARLY MORNING SATURDAY LEADING
TO A DRY FCST UNTIL SUNDAY AFTERNOON. AT THAT TIME POPS SLOWLY RAMP
UP ACROSS THE WESTERNMOST ZONES AS ANOTHER SYSTEM MOVES THROUGH THE
MID-SOUTH AND INTO THE TENNESSEE VALLEY. TEMPERATURES THROUGH THE
EXTENDED RANGE PERIOD WILL REMAIN AT OR JUST ABOVE NORMAL LEVELS
DESPITE THE FROPA FRIDAY EVENING.
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
AT KCLT...VFR STRATOCU AT AROUND 060 WILL LINGER NEAR THE AIRFIELD
THIS EVENING...GENERALLY REMAINING FEW/SCT...ALTHOUGH AN OCCL PERIOD
OF BKN IS POSSIBLE. OTHERWISE...NE WINDS WILL GRADUALLY DIMINISH
OVERNIGHT...BUT ARE EXPECTED TO REMAIN AT AROUND 5 KTS THROUGH AT
LEAST THE MORNING HOURS...BEFORE POSSIBLY VEERING TOWARD THE SE BY
THE END OF MONDAY.
ELSEWHERE...VFR CONDITIONS THROUGH THE PERIOD...WITH GRADUALLY
DIMINISHING NE WINDS EXPECTED. LIGHT/VARIABLE WINDS ARE EXPECTED IN
MANY AREAS MONDAY MORNING...BUT MAY BECOME LIGHT SE BY THE END OF
THE PERIOD.
OUTLOOK...A FAIRLY WET FRONTAL SYSTEM...WITH PIEDMONT
THUNDERSTORMS...IS EXPECTED ON TUE...WITH DRYING RETURNING MID WEEK.
CONFIDENCE TABLE...
00-06Z 06-12Z 12-18Z 18-24Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...SBK
NEAR TERM...JDL/MCAVOY
SHORT TERM...WIMBERLEY
LONG TERM...CDG
AVIATION...JDL
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
911 PM CDT SUN APR 20 2014
.UPDATE...
ISSUED AT 911 PM CDT SUN APR 20 2014
BAND OF SHOWERS AND THUNDERSTORMS ALONG FRONT AND LOW HAS BEEN
EXPANDING OVER THE WESTERN EDGE OF OUR FORECAST AREA. THIS IS IN
LINE WITH CURRENT PROJECTIONS BY THE HRRR AND EVEN THE RAP. LESS
CERTAIN IS HOW ACTIVITY WILL BEHAVE SOUTHEAST...IN NORTHWEST
IOWA...HAVING UNDERGONE A DECREASE LAST HOUR OR TWO...BUT EXPECT
SOME SEPARATE REGENERATION THERE AS THE LOW/FRONT APPROACH.
ANYWAY...THE MAIN CHANGE FOR NOW IS TO INCREASE POPS/COVERAGE OF
THE SHOWERS AND STORMS NORTH FROM THE EARLIER SLIGHT CHANCE.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 406 PM CDT SUN APR 20 2014
ELEVATED BAND OF SHOWERS AND ISOLATED THUNDERSTORMS DEVELOPING IN
NORTHEAST NEBRASKA THIS AFTERNOON AND GRADUALLY WORKING/DEVELOPING
NORTHEAST. NOT ANTICIPATING A WHOLE LOT OF ACTIVITY FROM THIS
CONVECTION BUT SHOULD PRODUCE SOME ISOLATED TO SCATTERED SHOWERS
WITH A FEW EMBEDDED THUNDERSTORMS. ANOTHER AREA LIKELY TO PRODUCE
ISOLATED ACTIVITY WILL BE IN CENTRAL SD NEAR AN INCOMING WEAK
CONVERGENT BOUNDARY. UPPER LEVEL SUPPORT NOT TOO GOOD AND DRY LOW
LEVELS SUGGEST THAT MAYBE NOTHING WILL GET GOING BUT STILL WORTH AN
ISOLATED THREAT AT THIS POINT.
THE MAIN AREA TO FOCUS ON WILL AGAIN BE NORTHWEST IOWA WHERE THERE
IS A BETTER COMBINATION OF UPPER LEVEL FORCING...INSTABILITY AND AND
LOW TO MID LEVEL FRONT. WILL KEEP LIKELIES GOING AND ALSO THE IDEA
THAT SEVERE THUNDERSTORMS WILL NOT BE A THREAT. CAPE VALUES MAY
APPROACH 500 TO 1000 J/KG THIS EVENING BUT WITH THE MODELS OVERDOING
THE LOW LEVEL MOISTURE THOSE VALUES COULD BE A BIT PESSIMISTIC. THE
BETTER CHANCES FOR PRECIPITATION SHOULD SHIFT SOUTHEAST OF THE AREA
LATE TONIGHT AS THE UPPER LEVEL WAVE TO THE NORTH BRINGS IN DRIER
AND MORE STABLE AIR. LOWS LIKELY TO RANGE FROM THE MID 40S IN THE
NORTHERN CWA TO THE MID 50S IN PARTS OF NORTHWEST IOWA.
THIS DRIER AND MORE STABLE AIR MASS WILL ALSO COME WITH A WELL MIXED
ATMOSPHERE AND DECENT PRESSURE GRADIENT WHICH WILL LEAD TO A WINDY
MONDAY IN MOST LOCATIONS. RECENT TRENDS IN GUIDANCE HAS BEEN TO
FORECAST DEW POINT TEMPERATURES TOO HIGH...ESPECIALLY IN A WELL
MIXED ENVIRONMENT SO WENT MUCH CLOSER TO THE BIAS CORRECTED OUTPUT
WHICH HAS BEEN HANDLING OUR DRY GROUND BETTER AS THE MODELS SEEM TO
BE HAVING TROUBLE WITH OUR DRIER THAN NORMAL BOUNDARY LAYER.
SO...BECAUSE OF THE LOW DEW POINTS AND HIGH WINDS WENT AHEAD AND
ISSUED A FIRE WEATHER WATCH FOR MOST OF THE AREA AS AFTERNOON
HUMIDITY VALUES LIKELY TO FALL BELOW 25 PERCENT IN MANY LOCATIONS AS
HIGHS CLIMB INTO THE UPPER 60S TO LOWER 70S.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 406 PM CDT SUN APR 20 2014
HIGH PRESSURE WILL CONTINUE TO EASE SOUTHWARD INTO THE REGION ON
MONDAY NIGHT. DIMINISHING WINDS AND MAINLY CLEAR SKIES...ALONG WITH
A DRIER AIRMASS SHOULD LEAD TO LOWS TOWARD THE LOWER END OF THE
FORECAST ENVELOPE...MAINLY MID TO UPPER 30S.
BY TUESDAY...UPPER LEVEL RIDGING WILL BUILD EASTWARD ACROSS THE AREA
ALONG WITH AN EASTWARD RETURN OF A FAIRLY STRONG MID LEVEL FRONTAL
ZONE. MOISTURE IS PRETTY ANEMIC THROUGH THE DAY AT LOWER LEVELS...
BUT ELEVATED PARCELS AROUND 700 HPA OR A BIT HIGHER DO INDICATE
SOME CONVECTIVE INSTABILITY. HAVE NOT INCLUDED ANY PRECIPITATION
WORKING SLOWLY EASTWARD ACROSS THE CWA...BUT WOULD CERTAINLY THINK
AT LEAST A COUPLE OF SPRINKLES WOULD ACCOMPANY THE THICKENING MID
CLOUDS THROUGH THE DAY TOWARD AT LEAST I29 BY LATE DAY. SHADED
DEWPOINT FORECAST TOWARD DRIER RAW PROFILES...AS HAS BEEN THE CASE
OF LATE.
STRONG LOW LEVEL JET OF 50 TO 60 KNOTS DEVELOPS ON TUESDAY NIGHT
WITH MOISTURE SURGE WORKING RAPIDLY NORTHWARD FROM THE SOUTHERN
HIGH PLAINS. FAIRLY GOOD WAVE MOVING THROUGH RIDGE DURING THE
NIGHT...MAIN CONVERGENCE WITH LOW LEVEL JET ESTABLISHES
NORTH...BUT CONTINUED MID LEVEL INSTABILITY WITH 8-9C/KM AND
INCREASING MOISTURE SUGGESTS A BETTER COVERAGE OF SHOWERS AND
ISOLATED THUNDER WITH TIME OVERNIGHT. WINDS WILL ALSO BECOME AN
ISSUE LATER IN THE NIGHT...AND COULD GET SOMEWHAT CLOSE TO WIND
ADVISORY NEAR AND WEST OF I 29...AND EXPANDING OVER MUCH OF THE
AREA DURING THE DAY ON WEDNESDAY.
LAPSE RATES REMAIN STEEP INTO THE DAYTIME...BUT GRADUALLY MODIFY A
BIT MIDDAY WITH WARMER LAYER ALOFT BUILDING IN...WHICH COULD WORK
TO SLOW UP OR EVEN END CONVECTION FROM SOUTHWEST TO NORTHEAST DURING
THE MORNING AND LINGERING INTO THE AFTERNOON. SHOULD KEEP A FAIR
AMOUNT OF CLOUDS AROUND WITH STRONG LOW LEVEL JET...ESPECIALLY
ACROSS SOUTHWEST MINNESOTA INTO NORTHWEST IOWA. IF IT BREAKS
OUT... COULD BE APPRECIABLY WARMER AND GENERATE MORE INSTABILITY
BY WEDNESDAY AFTERNOON...TO CORRELATE WITH APPROACH OF STRONGER
UPPER LIFT FORCING AND CONVERGENT BOUNDARY TOWARD THE JAMES VALLEY
BY LATER IN THE DAY. WOULD CERTAINLY MAINTAIN AT LEAST A SMALL
SEVERE WEATHER THREAT GIVEN THE SHEAR AND INSTABILITY
POTENTIAL...ESPECIALLY FROM THE LOWER JAMES AND BIG SIOUX VALLEY
EASTWARD. TROUGH WILL LIFT PAST WEDNESDAY NIGHT...WITH DYNAMICS
SUPPORTIVE OF HIGHER POPS EAST OF THE JAMES RIVER...AND ESPECIALLY
ACROSS NORTHWEST IOWA. PRECIP THREAT GRADUALLY TAPERING OFF WEST
TO EAST OVERNIGHT...LINGERING IN THE FAR EASTERN CWA INTO THURSDAY
MORNING. UPPER LOW CONTINUES TO DEEPEN AND CLOSE OFF NORTHEAST
OF THE AREA ON THURSDAY...PLACING AREA IN A MORE SUBSIDENT FAVORED
QUADRANT WITH MOISTURE DISPLACED TO THE NORTH/EAST. HAVE TRIMMED
BACK POPS SOMEWHAT...ESPECIALLY THROUGH THE MISSOURI VALLEY...AND
TAKEN TEMPS CLOSER THE 850 HPA MIXING OF DRIER SOLUTIONS.
HANDLING OF THE INTENSE UPPER TROUGH...AND NEXT ONE LATER IN THE
WEEKEND...IS WIDELY VARIED BETWEEN MODELS AND LEADS TO QUITE LOW
CONFIDENCE IN THE OVERALL PATTERN FROM FRIDAY THROUGH SUNDAY.
COULD EVEN FIND THREAT FOR A LITTLE SNOWFALL WITHOUT STRAYING TOO
FAR FROM A COUPLE SOLUTIONS...BUT WAY TOO FAR OUT TO PUT ANY FAITH
IN THE FORECAST. DOES APPEAR AS IF IT WILL BE AN ACTIVE TIME LATER
IN THE WEEKEND...AND WITH THE ABUNDANCE OF CLOUDS AND OR COOLER
AIR IN PLACE...HAVE KEPT NEAR TO A BIT ON THE COOLER SIDE OF
GUIDANCE FOR THE WEEKEND.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 653 PM CDT SUN APR 20 2014
VFR WILL PREVAIL TONIGHT THROUGH MONDAY. THERE WILL BE
THUNDERSTORMS IN NORTHWEST IOWA...THE QUESTION IS HOW LONG THEY
WILL LAST. THEY COULD LAST OFF AND ON FOR A BULK OF THE NIGHT. BUT
FOR THE KSUX TAF SITE...OPTED TO ONLY INCLUDE TWO HOURS OF TSRA
EARLY THIS EVENING COINCIDING WITH THE DAYTIME HEATING...THEN GAVE
THEM A BREAK. CONTINUED TO INCLUDE JUST SHOWERS FOR NOW LATER
TONIGHT AT KSUX WHEN THE SURFACE WIND SHIFT/COLD FRONT COMES
THROUGH. BUT ADMITTEDLY THERE IS ENOUGH ELEVATED INSTABILITY THAT
THERE COULD BE SOME ISOLATED TSRA IN THAT AREA AGAIN SHORTLY AFTER
MIDNIGHT. OTHERWISE...ALSO INCLUDED A BRIEF WINDOW OF LIGHT TSRA
AT THE KHON TAF SITE LATE THIS EVENING COINCIDING WITH THE WIND
SHIFT LINE...AS THERE IS SOME ELEVATED THUNDERSTORMS IN CENTRAL SD
RIGHT NOW. IF THEY DO NOT HOLD TOGETHER AFTER SUNSET THOUGH...WILL
UPDATE THE KHON TAF AND ELIMINATE THEM. FINALLY FOR KFSD...HAVE SHOWERS
IN OVERNIGHT BUT NOT THUNDER...AGAIN COINCIDING WITH THE WIND
SHIFT. ACTIVITY SHOULD BE LESS CONVECTIVE BY THEN.
&&
.FIRE WEATHER...
ISSUED AT 406 PM CDT SUN APR 20 2014
A STRONG NORTHWEST WIND WILL DEVELOP THROUGH THE MORNING ON MONDAY
IN A WELL MIXED ATMOSPHERE...LEADING TO DANGEROUS FIRE WEATHER
CONDITIONS. AFTERNOON RELATIVE HUMIDITIES WILL LIKELY DROP TO
BETWEEN 20 AND 25 PERCENT OF THE ENTIRE AREA WITH WINDS AVERAGING
ABOUT 20 TO 30 MPH AND A FEW GUSTS AROUND 35 MPH. SOUTH CENTRAL SD
WILL SEE WINDS MORE IN LINE WITH 15 TO 25 MPH AND WITH EXPECTED
RELATIVE HUMIDITY VALUES ABOVE 20 PERCENT A VERY HIGH FIRE DANGER
WILL BE MAINTAINED. THIS MOST DANGEROUS FIRE WEATHER CONDITIONS
SHOULD BE FROM ABOUT 100 PM TO 700 PM ON MONDAY. DEW POINTS MAY END
UP JUST A BIT HIGHER BUT THE TRENDS SO FAR THIS SPRING HAVE BEEN FOR
THE GUIDANCE TO OVER FORECAST DEW POINTS BY ABOUT 3 TO 6 DEGREES SO
TOOK THIS INTO ACCOUNT.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...FIRE WEATHER WATCH FROM MONDAY AFTERNOON THROUGH MONDAY EVENING
FOR SDZ256>258.
MN...FIRE WEATHER WATCH FROM MONDAY AFTERNOON THROUGH MONDAY EVENING
FOR MNZ900.
IA...FIRE WEATHER WATCH FROM MONDAY AFTERNOON THROUGH MONDAY EVENING
FOR IAZ300-301.
NE...FIRE WEATHER WATCH FROM MONDAY AFTERNOON THROUGH MONDAY EVENING
FOR NEZ249.
&&
$$
UPDATE...
SHORT TERM...08
LONG TERM...CHAPMAN
AVIATION...MJ
FIRE WEATHER...08
AREA FORECAST DISCUSSION...UPDATED
NWS ABERDEEN SD
706 PM CDT SUN APR 20 2014
.UPDATE...
CURRENT RADAR SHOWS AN AREA OF TSTORMS MOVING THROUGH LYMAN AND
SOUTHERN HUGHES COUNTY. LIKE THE HRRR DEPICTION OF CONVECTIVE
PROGRESSION EASTWARD SO NUDGED POPS A BIT TO REFLECT THE 21Z
GUIDANCE. EVEN THOUGH RADAR IS ALSO SHOWING SOME WEAK RETURNS
ACROSS THE EASTERN CWA KEPT THIS AREA DRY. DUE TO THE 35 DEGREE
DEWPOINT SPREAD AND THE LACK OF ANY STRONG ECHOES THIS ACTIVITY IS
LIKELY ALL VIRGA IN THE EAST FOR NOW.
DROPPED OVERNIGHT LOWS ABOUT FIVE DEGREES IN THE NORTH...FROM THE
JAMES VALLEY TO CORSON COUNTY. EVEN WITH MOISTER AID ADVECTING IN
FROM THE WEST ACROSS THE SOUTH...NORTHERN UPSTREAM OBS HAVE
DEWPOINTS IN THE 20S TO LOWER 30S WHICH SHOULD ALLOW TEMPERATURES
TO TANK AFTER SUNSET SINCE WINDS ARE LIGHT.
SEE UPDATED AVIATION DISCUSSION BELOW.
&&
.PREVIOUS DISCUSSION...
.SHORT TERM...TONIGHT THROUGH TUESDAY NIGHT
A WEAK LOW PRESSURE SYSTEM AND ASSOCIATED COOL FRONT WILL TRACK
ACROSS THE AREA TONIGHT. FAIRLY WARM TEMPERATURES HAVE AIDED IN A
LITTLE INSTABILITY DEVELOPMENT ACROSS THE SOUTHERN PORTION OF THE
STATE...AND MAY SEE SOME SHOWER AND THUNDERSTORM DEVELOPMENT THIS
EVENING OVER THE SOUTHERN CWA. MOISTURE IS PRETTY LIMITED...SO NOT
ANTICIPATING ANY SEVERE WEATHER. HIGH PRESSURE MOVES IN BEHIND THE
EXITING LOW ON MONDAY. EVEN THOUGH TEMPERATURES WILL BE A BIT
COOLER...DECENT MIXING WILL BRING BREEZY TO WINDY CONDITIONS TO
THE EASTERN CWA...AND WITH THE DRIER AIR IN PLACE...THE POTENTIAL
IS THERE FOR FIRE WEATHER ISSUES. THEREFORE...HAVE ISSUED A FIRE
WEATHER WATCH FOR THE EASTERN CWA...INCLUDING THE TWO MINNESOTA
COUNTIES FOR MONDAY AFTERNOON. AFTER THAT...THINGS STAY QUIET
UNTIL TUESDAY NIGHT WHEN WARM FRONTAL RAIN SHOWERS LOOK TO AFFECT
MUCH OF THE CWA AHEAD OF ANOTHER APPROACHING LOW...ALONG WITH
GUSTY WINDS SPREADING FROM WEST TO EAST.
WITH THE HIGH DOMINANT ON MONDAY...SLIGHTLY COOLER TEMPS IN THE
60S WILL BE COMMON FOR HIGHS...WITH JUST A BIT OF A RISE IN HIGHS
ON TUESDAY...MAINLY MID 60S TO LOWER 70S. OVERNIGHT LOWS WILL BE
MAINLY IN THE 40S TONIGHT AND TUESDAY NIGHT...WITH COOLER 30S
EXPECTED MONDAY NIGHT.
.LONG TERM...WEDNESDAY THROUGH SUNDAY
THE MEDIUM RANGE MODELS CONTINUE TO SHOW A PROGRESSIVE PATTERN
THROUGH THE EXTENDED PERIOD. TIMING OF PRECIP WILL BE TRICKY AS
DETAILS DIFFER ALONG WITH THE PRESENCE OF A DRY SLOT WEDNESDAY AND
THURSDAY AS THE UPPER LOW PUSHES INTO NE MT. HAVE TRENDED
THUNDERSTORM CHANCES HIGHEST IN THE EAST WHERE DRY SLOT INFLUENCE
APPEARS TO BE NOT AS STRONG. MODELS DIFFER ON WHAT THIS UPPER WILL
DO...EC HAS IT WEAKENING THEN REORGANIZING IT OVER NORTHERN MN.
EXPECT SHOWERS ON BACKSIDE OF LOW FRIDAY. CONFIDENCE LOW ON
POSITION OF DRY SLOT AT THIS TIME BUT WILL HAVE TO BE WATCHED AS
IT WILL PLAY A BIG ROLE ON WHAT AREAS STAY ON THE DRIER SIDE.
THE UPPER RIDGE LOOKS TO POP BACK INTO THE AREA SATURDAY WITH
SHOWERS AND THUNDERSTORMS DEVELOPING AGAIN SATURDAY
AFTERNOON/NIGHT AS FLOW QUICKLY BECOMES SOUTHWEST ALOFT. TEMPS
WILL HAVE A HARD TIME REBOUNDING IN THE RIDGE WITH COOLER AIR IN
PLACE AND A QUICK RETURN OF CLOUDS AND PRECIPITATION CHANCES.
&&
.AVIATION...
00Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS
VFR CONDITIONS WILL PREVAIL THROUGH THE TAF PERIOD. A WEAK FRONT
WILL MOVE THROUGH THE REGION OVERNIGHT TURNING WINDS TO THE
NORTHWEST. DID ADD SOME VCTS TO KPIR AS STORMS HAVE BEEN
DEVELOPING AND MOVING JUST TO THE SOUTH OF THE METAR SITE. STORMS
SHOULD MOVE OUT OF THE AREA OVER THE NEXT COUPLE OF HOURS. NO
RESTRICTIONS TO CIGS OR VSBYS ARE ANTICIPATED AND ONLY ISOLATED
SHOWERS ARE EXPECTED IN THE VCNTY OF KATY AFT 03Z. NORTHWEST WINDS
WILL BECOME GUSTY IN THE MORNING AT 15 TO 25 KTS AT ALL SITES BY
LATE MORNING MONDAY.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...FIRE WEATHER WATCH FROM MONDAY AFTERNOON THROUGH MONDAY EVENING
FOR PRAIRIE COTEAU-RED RIVER VALLEY-UPPER JAMES RIVER.
MN...FIRE WEATHER WATCH FROM MONDAY AFTERNOON THROUGH MONDAY EVENING
FOR BIG STONE-TRAVERSE.
&&
$$
UPDATE...WISE
SHORT TERM...PARKIN
LONG TERM...SCARLETT
AVIATION...WISE
WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
1259 PM CDT SAT APR 19 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 342 AM CDT SAT APR 19 2014
ONCE AGAIN DRY SUB-CLOUD LAYER PREVENTING ANY ATTEMPT AT PRECIP FROM
REALLY REACHING THE SURFACE EARLY THIS MORNING...AND WITH MID LEVEL
WAVE SHEARING OFF TO THE NORTHEAST RESULTING IN CONTINUED WEAKENING
SUPPORT...HAVE PULLED ANY MEASURABLE POPS FROM THE MORNING. WILL
CARRY A FEW SPRINKLES FOR NOW...BUT MAY EVEN BE ABLE TO PULL ALL
PRECIP MENTION FOR THE MORNING HOURS IF CURRENT TRENDS CONTINUE.
OTHERWISE TODAY SHOULD BE QUITE MILD WITH DECENT MIXING EXPECTED IN
SOUTHWEST FLOW AHEAD OF APPROACHING TROUGH AXIS...POISED JUST WEST
OF THE CWA AT 08Z. EVEN BEHIND THE BOUNDARY...WHICH IS EXPECTED TO
BE NEAR A KMML-KFSD-KYKN LINE BY LATE AFTERNOON...MODELS INDICATE
LITTLE SIGNIFICANT LOW LEVEL COOLING. WITH FAIR MIXING IN THE WEST
TO NORTHWEST FLOW...AS WELL AS GREATER AMOUNT OF SUNSHINE AND DRIER
LOW LEVELS...SHOULD STILL SEE VERY MILD TEMPERATURES AND WILL AGAIN
FAVOR WARMER RAP AND BIAS-CORRECTED RAW MODEL TEMPS FOR HIGHS THIS
AFTERNOON. EXPECT MOST AREAS TO CLIMB INTO THE 70S...AND WOULD NOT
BE SURPRISED TO SEE AN 80+ DEGREE READING IN OUR FAR SOUTH THOUGH
KEEPING HIGHS JUST SHY FOR NOW. MIXY SOUTHWEST FLOW AND WARM TEMPS
EAST OF THE BOUNDARY LEAD TO VERY HIGH FIRE DANGER EAST OF HIGHWAY
60 CORRIDOR IN NORTHWEST IOWA/SOUTHWEST MINNESOTA...THOUGH WITH THE
WINDS EXPECTED TO DIMINISH WITH APPROACH OF BOUNDARY...AND LOW LEVEL
MOISTURE BEGINNING TO POOL NEAR/SOUTH OF THE BOUNDARY...CONDITIONS
SHOULD ACTUALLY IMPROVE AS THE AFTERNOON PROGRESSES.
WILL HANG ONTO LOW POPS IN OUR SOUTHEAST THIS AFTERNOON AS WEAK MID
LEVEL WAVE LIFTS NORTHEAST ALONG THE BOUNDARY...THOUGH INSTABILITY
PRETTY WEAK SO WILL HAVE ONLY ISOLATED THUNDER MENTION. BOUNDARY
SAGS SLIGHTLY FARTHER SOUTHEAST AND STALLS ACROSS OUR FAR SOUTHEAST
TONIGHT. WITH CONTINUED SOUTHERLY LOW LEVEL MOISTURE TRANSPORT INTO
THE BOUNDARY...AND ANOTHER WEAK WAVE GETTING KICKED OUT OF SOUTHERN
ROCKIES TROUGH...WILL GRADUALLY RAMP UP POPS THROUGH THE OVERNIGHT
HOURS...THOUGH BOUNDARY FORECAST TO PUSH A LITTLE FARTHER SOUTHEAST
THAN PREVIOUSLY INDICATED...SO POPS LIKEWISE A LITTLE FARTHER SOUTH
AND EXPECT ANY NIGHTTIME SHOWERS TO REMAIN SOUTH OF KFSD. AMERICAN
MODELS QUITE A BIT MORE BULLISH ON PRECIP AMOUNTS THAN GEM/ECMWF...
WHICH ALSO DECREASES CONFIDENCE IN POTENTIAL FOR MORE WIDESPREAD
SHOWERS...AND THUS TRIMMED HIGHEST POPS BACK INTO LIKELY RANGE.
POOLED MOISTURE ALONG THE BOUNDARY AS WELL AS EXTENSIVE CLOUD COVER
SHOULD HOLD LOWS TONIGHT IN THE LOWER TO MID 50S ACROSS SOUTHEAST
CWA...WHILE DRIER AIR/LIGHT WINDS IN OUR NORTHWEST ALLOW READINGS TO
FALL INTO THE LOWER 40S.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 342 AM CDT SAT APR 19 2014
THE FRONTAL BOUNDARY WILL REMAIN STALLED ACROSS OUR SOUTHEAST ON
SUNDAY AND SUNDAY NIGHT...KEEPING THE FOCUS FOR SHOWERS AND
THUNDERSTORMS OVER THAT AREA DURING THE PERIOD AS A SOUTHERN STREAM
WAVE BEGINS TO LIFT UP INTO THE REGION. WHILE THERE MAY BE A BREAK
IN THE ACTIVITY ON SUNDAY MORNING...EXPECT CHANCES TO INCREASE ON
SUNDAY AFTERNOON AND EVENING AS THE AFOREMENTIONED SHORTWAVE BEGINS
TO EXERT MORE INFLUENCE AND BETTER INSTABILITY NUDGES INTO OUR
SOUTH. WILL SEE SOME LOCALLY HEAVY RAIN POSSIBLE IN HEAVIER ACTIVITY
WITH PWAT VALUES RUNNING AROUND AN INCH AND A QUARTER. AREAS FARTHER
TO THE NORTH AND WEST WILL ACTUALLY HAVE A DECENT DAY ON SUNDAY AS
AFTERNOON TEMPERATURES MIX OUT INTO THE LOWER TO MID 70S...WHILE
AREAS AFFECTED BY CLOUD COVER/SHOWERS WILL ONLY MAKE IT UP INTO THE
MID AND UPPER 60S. BY LATE SUNDAY NIGHT THE BOUNDARY FINALLY
BEGINS TO SAG TO THE SOUTH AS THE UPPER LEVEL TROUGH PULLS TO THE
EAST...WITH AND SHOWERS AND ISOLATED THUNDERSTORMS DIMINISHING
TOWARD EARLY MONDAY MORNING. LOWS WILL REMAIN RELATIVELY
MILD...DROPPING INTO THE LOWER 40S THROUGH THE WESTERN AND CENTRAL
HIGHWAY CORRIDOR TO THE LOWER 50S THROUGH THE SIOUX CITY TO STORM
LAKE AREA.
SURFACE RIDGING THEN SLIDES ACROSS THE REGION FOR MONDAY AND TUESDAY
WITH TEMPERATURES DROPPING BACK A BIT IN A COLD AIR ADVECTION REGIME.
LOOKING AT HIGHS IN THE 60S TO NEAR 70 BOTH DAYS. IT WILL BE BREEZY
ON MONDAY WITH GOOD MIXING AND WINDS RUNNING AROUND 25 TO 30 KTS AT
THE TOP OF THE MIXED LAYER.
INTO THE EXTENDED...MORE SIGNIFICANT SYSTEM FOR THE MIDDLE OF THE
UPCOMING WEEK AS AN UPPER LEVEL TROUGH OVER THE WESTERN U.S NUDGES
EASTWARD. MODEL CONSENSUS WOULD PUT THE BULLSEYE FOR BEST
PRECIPITATION CHANCES ACROSS THE AREA IN THE WEDNESDAY NIGHT TO
THURSDAY TIMEFRAME AS THE MAIN UPPER LEVEL FORCING AND LOWER LEVEL
FRONTAL DYNAMICS COME TOGETHER. DOES APPEAR TO BE FAIRLY WINDY
THROUGH THE WEDNESDAY TO FRIDAY TIMEFRAME...WITH TEMPERATURES
TRENDING DOWNWARD BY THE END OF THE WEEK WITH THE PASSAGE OF THE
SYSTEM.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1258 PM CDT SAT APR 19 2014
MAINLY VFR CONDITIONS THROUGH THE PERIOD. ISOLATED THUNDERSTORMS
WILL BE POSSIBLE MAINLY AROUND THE KSUX AREA LATE TONIGHT BUT
CHANCES ARE SMALL ENOUGH THE ONLY SHOWERS WILL BE MENTIONED FOR
NOW.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
SHORT TERM...JH
LONG TERM...JM
AVIATION...08
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
639 AM CDT SAT APR 19 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 342 AM CDT SAT APR 19 2014
ONCE AGAIN DRY SUB-CLOUD LAYER PREVENTING ANY ATTEMPT AT PRECIP FROM
REALLY REACHING THE SURFACE EARLY THIS MORNING...AND WITH MID LEVEL
WAVE SHEARING OFF TO THE NORTHEAST RESULTING IN CONTINUED WEAKENING
SUPPORT...HAVE PULLED ANY MEASURABLE POPS FROM THE MORNING. WILL
CARRY A FEW SPRINKLES FOR NOW...BUT MAY EVEN BE ABLE TO PULL ALL
PRECIP MENTION FOR THE MORNING HOURS IF CURRENT TRENDS CONTINUE.
OTHERWISE TODAY SHOULD BE QUITE MILD WITH DECENT MIXING EXPECTED IN
SOUTHWEST FLOW AHEAD OF APPROACHING TROUGH AXIS...POISED JUST WEST
OF THE CWA AT 08Z. EVEN BEHIND THE BOUNDARY...WHICH IS EXPECTED TO
BE NEAR A KMML-KFSD-KYKN LINE BY LATE AFTERNOON...MODELS INDICATE
LITTLE SIGNIFICANT LOW LEVEL COOLING. WITH FAIR MIXING IN THE WEST
TO NORTHWEST FLOW...AS WELL AS GREATER AMOUNT OF SUNSHINE AND DRIER
LOW LEVELS...SHOULD STILL SEE VERY MILD TEMPERATURES AND WILL AGAIN
FAVOR WARMER RAP AND BIAS-CORRECTED RAW MODEL TEMPS FOR HIGHS THIS
AFTERNOON. EXPECT MOST AREAS TO CLIMB INTO THE 70S...AND WOULD NOT
BE SURPRISED TO SEE AN 80+ DEGREE READING IN OUR FAR SOUTH THOUGH
KEEPING HIGHS JUST SHY FOR NOW. MIXY SOUTHWEST FLOW AND WARM TEMPS
EAST OF THE BOUNDARY LEAD TO VERY HIGH FIRE DANGER EAST OF HIGHWAY
60 CORRIDOR IN NORTHWEST IOWA/SOUTHWEST MINNESOTA...THOUGH WITH THE
WINDS EXPECTED TO DIMINISH WITH APPROACH OF BOUNDARY...AND LOW LEVEL
MOISTURE BEGINNING TO POOL NEAR/SOUTH OF THE BOUNDARY...CONDITIONS
SHOULD ACTUALLY IMPROVE AS THE AFTERNOON PROGRESSES.
WILL HANG ONTO LOW POPS IN OUR SOUTHEAST THIS AFTERNOON AS WEAK MID
LEVEL WAVE LIFTS NORTHEAST ALONG THE BOUNDARY...THOUGH INSTABILITY
PRETTY WEAK SO WILL HAVE ONLY ISOLATED THUNDER MENTION. BOUNDARY
SAGS SLIGHTLY FARTHER SOUTHEAST AND STALLS ACROSS OUR FAR SOUTHEAST
TONIGHT. WITH CONTINUED SOUTHERLY LOW LEVEL MOISTURE TRANSPORT INTO
THE BOUNDARY...AND ANOTHER WEAK WAVE GETTING KICKED OUT OF SOUTHERN
ROCKIES TROUGH...WILL GRADUALLY RAMP UP POPS THROUGH THE OVERNIGHT
HOURS...THOUGH BOUNDARY FORECAST TO PUSH A LITTLE FARTHER SOUTHEAST
THAN PREVIOUSLY INDICATED...SO POPS LIKEWISE A LITTLE FARTHER SOUTH
AND EXPECT ANY NIGHTTIME SHOWERS TO REMAIN SOUTH OF KFSD. AMERICAN
MODELS QUITE A BIT MORE BULLISH ON PRECIP AMOUNTS THAN GEM/ECMWF...
WHICH ALSO DECREASES CONFIDENCE IN POTENTIAL FOR MORE WIDESPREAD
SHOWERS...AND THUS TRIMMED HIGHEST POPS BACK INTO LIKELY RANGE.
POOLED MOISTURE ALONG THE BOUNDARY AS WELL AS EXTENSIVE CLOUD COVER
SHOULD HOLD LOWS TONIGHT IN THE LOWER TO MID 50S ACROSS SOUTHEAST
CWA...WHILE DRIER AIR/LIGHT WINDS IN OUR NORTHWEST ALLOW READINGS TO
FALL INTO THE LOWER 40S.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 342 AM CDT SAT APR 19 2014
THE FRONTAL BOUNDARY WILL REMAIN STALLED ACROSS OUR SOUTHEAST ON
SUNDAY AND SUNDAY NIGHT...KEEPING THE FOCUS FOR SHOWERS AND
THUNDERSTORMS OVER THAT AREA DURING THE PERIOD AS A SOUTHERN STREAM
WAVE BEGINS TO LIFT UP INTO THE REGION. WHILE THERE MAY BE A BREAK
IN THE ACTIVITY ON SUNDAY MORNING...EXPECT CHANCES TO INCREASE ON
SUNDAY AFTERNOON AND EVENING AS THE AFOREMENTIONED SHORTWAVE BEGINS
TO EXERT MORE INFLUENCE AND BETTER INSTABILITY NUDGES INTO OUR
SOUTH. WILL SEE SOME LOCALLY HEAVY RAIN POSSIBLE IN HEAVIER ACTIVITY
WITH PWAT VALUES RUNNING AROUND AN INCH AND A QUARTER. AREAS FARTHER
TO THE NORTH AND WEST WILL ACTUALLY HAVE A DECENT DAY ON SUNDAY AS
AFTERNOON TEMPERATURES MIX OUT INTO THE LOWER TO MID 70S...WHILE
AREAS AFFECTED BY CLOUD COVER/SHOWERS WILL ONLY MAKE IT UP INTO THE
MID AND UPPER 60S. BY LATE SUNDAY NIGHT THE BOUNDARY FINALLY
BEGINS TO SAG TO THE SOUTH AS THE UPPER LEVEL TROUGH PULLS TO THE
EAST...WITH AND SHOWERS AND ISOLATED THUNDERSTORMS DIMINISHING
TOWARD EARLY MONDAY MORNING. LOWS WILL REMAIN RELATIVELY
MILD...DROPPING INTO THE LOWER 40S THROUGH THE WESTERN AND CENTRAL
HIGHWAY CORRIDOR TO THE LOWER 50S THROUGH THE SIOUX CITY TO STORM
LAKE AREA.
SURFACE RIDGING THEN SLIDES ACROSS THE REGION FOR MONDAY AND TUESDAY
WITH TEMPERATURES DROPPING BACK A BIT IN A COLD AIR ADVECTION REGIME.
LOOKING AT HIGHS IN THE 60S TO NEAR 70 BOTH DAYS. IT WILL BE BREEZY
ON MONDAY WITH GOOD MIXING AND WINDS RUNNING AROUND 25 TO 30 KTS AT
THE TOP OF THE MIXED LAYER.
INTO THE EXTENDED...MORE SIGNIFICANT SYSTEM FOR THE MIDDLE OF THE
UPCOMING WEEK AS AN UPPER LEVEL TROUGH OVER THE WESTERN U.S NUDGES
EASTWARD. MODEL CONSENSUS WOULD PUT THE BULLSEYE FOR BEST
PRECIPITATION CHANCES ACROSS THE AREA IN THE WEDNESDAY NIGHT TO
THURSDAY TIMEFRAME AS THE MAIN UPPER LEVEL FORCING AND LOWER LEVEL
FRONTAL DYNAMICS COME TOGETHER. DOES APPEAR TO BE FAIRLY WINDY
THROUGH THE WEDNESDAY TO FRIDAY TIMEFRAME...WITH TEMPERATURES
TRENDING DOWNWARD BY THE END OF THE WEEK WITH THE PASSAGE OF THE
SYSTEM.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 639 AM CDT SAT APR 19 2014
SOUTHERLY WIND GUSTS OF 20-30KT STILL LIKELY ALONG AND EAST OF I-29
CORRIDOR INTO THIS AFTERNOON...BUT SHOULD GRADUALLY DIMINISH WEST TO
EAST AS SURFACE TROUGH PUSHES EAST. WESTERN PARTS OF THE AREA SHOULD
GENERALLY SEE LIGHTER WINDS THROUGH THE PERIOD...THOUGH BRIEF GUSTS
OF 25-30KT POSSIBLE AS SPRINKLES OR LIGHT SHOWERS SLIDE EAST ACROSS
THE REGION THIS MORNING.
AS THE BOUNDARY MOVES INTO MN/IA THIS AFTERNOON/TONIGHT...COULD SEE A
FEW SHOWERS OR EVEN AN ISOLATED THUNDERSTORM...THOUGH THREAT AT TAF
LOCATIONS TOO LOW TO FEEL CONFIDENT IN MENTIONING PRIOR TO 06Z. AFTER
06Z...COVERAGE EXPECTED TO INCREASE NEAR AND SOUTH OF THE BOUNDARY IN
NORTHWEST IOWA...AND HAVE ADDED -SHRA INTO KSUX TAF FOR THE PRE-DAWN
HOURS SUNDAY. ISOLATED TSRA POSSIBLE WITH THIS ACTIVITY...BUT AGAIN
WITH LOW CONFIDENCE IN TSRA COVERAGE...OPTED TO JUST STICK WITH SHRA
FOR NOW. CEILINGS/VISIBILITY EXPECTED TO REMAIN VFR.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
SHORT TERM...JH
LONG TERM...JM
AVIATION...JH
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
343 AM CDT SAT APR 19 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 342 AM CDT SAT APR 19 2014
ONCE AGAIN DRY SUB-CLOUD LAYER PREVENTING ANY ATTEMPT AT PRECIP FROM
REALLY REACHING THE SURFACE EARLY THIS MORNING...AND WITH MID LEVEL
WAVE SHEARING OFF TO THE NORTHEAST RESULTING IN CONTINUED WEAKENING
SUPPORT...HAVE PULLED ANY MEASURABLE POPS FROM THE MORNING. WILL
CARRY A FEW SPRINKLES FOR NOW...BUT MAY EVEN BE ABLE TO PULL ALL
PRECIP MENTION FOR THE MORNING HOURS IF CURRENT TRENDS CONTINUE.
OTHERWISE TODAY SHOULD BE QUITE MILD WITH DECENT MIXING EXPECTED IN
SOUTHWEST FLOW AHEAD OF APPROACHING TROUGH AXIS...POISED JUST WEST
OF THE CWA AT 08Z. EVEN BEHIND THE BOUNDARY...WHICH IS EXPECTED TO
BE NEAR A KMML-KFSD-KYKN LINE BY LATE AFTERNOON...MODELS INDICATE
LITTLE SIGNIFICANT LOW LEVEL COOLING. WITH FAIR MIXING IN THE WEST
TO NORTHWEST FLOW...AS WELL AS GREATER AMOUNT OF SUNSHINE AND DRIER
LOW LEVELS...SHOULD STILL SEE VERY MILD TEMPERATURES AND WILL AGAIN
FAVOR WARMER RAP AND BIAS-CORRECTED RAW MODEL TEMPS FOR HIGHS THIS
AFTERNOON. EXPECT MOST AREAS TO CLIMB INTO THE 70S...AND WOULD NOT
BE SURPRISED TO SEE AN 80+ DEGREE READING IN OUR FAR SOUTH THOUGH
KEEPING HIGHS JUST SHY FOR NOW. MIXY SOUTHWEST FLOW AND WARM TEMPS
EAST OF THE BOUNDARY LEAD TO VERY HIGH FIRE DANGER EAST OF HIGHWAY
60 CORRIDOR IN NORTHWEST IOWA/SOUTHWEST MINNESOTA...THOUGH WITH THE
WINDS EXPECTED TO DIMINISH WITH APPROACH OF BOUNDARY...AND LOW LEVEL
MOISTURE BEGINNING TO POOL NEAR/SOUTH OF THE BOUNDARY...CONDITIONS
SHOULD ACTUALLY IMPROVE AS THE AFTERNOON PROGRESSES.
WILL HANG ONTO LOW POPS IN OUR SOUTHEAST THIS AFTERNOON AS WEAK MID
LEVEL WAVE LIFTS NORTHEAST ALONG THE BOUNDARY...THOUGH INSTABILITY
PRETTY WEAK SO WILL HAVE ONLY ISOLATED THUNDER MENTION. BOUNDARY
SAGS SLIGHTLY FARTHER SOUTHEAST AND STALLS ACROSS OUR FAR SOUTHEAST
TONIGHT. WITH CONTINUED SOUTHERLY LOW LEVEL MOISTURE TRANSPORT INTO
THE BOUNDARY...AND ANOTHER WEAK WAVE GETTING KICKED OUT OF SOUTHERN
ROCKIES TROUGH...WILL GRADUALLY RAMP UP POPS THROUGH THE OVERNIGHT
HOURS...THOUGH BOUNDARY FORECAST TO PUSH A LITTLE FARTHER SOUTHEAST
THAN PREVIOUSLY INDICATED...SO POPS LIKEWISE A LITTLE FARTHER SOUTH
AND EXPECT ANY NIGHTTIME SHOWERS TO REMAIN SOUTH OF KFSD. AMERICAN
MODELS QUITE A BIT MORE BULLISH ON PRECIP AMOUNTS THAN GEM/ECMWF...
WHICH ALSO DECREASES CONFIDENCE IN POTENTIAL FOR MORE WIDESPREAD
SHOWERS...AND THUS TRIMMED HIGHEST POPS BACK INTO LIKELY RANGE.
POOLED MOISTURE ALONG THE BOUNDARY AS WELL AS EXTENSIVE CLOUD COVER
SHOULD HOLD LOWS TONIGHT IN THE LOWER TO MID 50S ACROSS SOUTHEAST
CWA...WHILE DRIER AIR/LIGHT WINDS IN OUR NORTHWEST ALLOW READINGS TO
FALL INTO THE LOWER 40S.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 342 AM CDT SAT APR 19 2014
THE FRONTAL BOUNDARY WILL REMAIN STALLED ACROSS OUR SOUTHEAST ON
SUNDAY AND SUNDAY NIGHT...KEEPING THE FOCUS FOR SHOWERS AND
THUNDERSTORMS OVER THAT AREA DURING THE PERIOD AS A SOUTHERN STREAM
WAVE BEGINS TO LIFT UP INTO THE REGION. WHILE THERE MAY BE A BREAK
IN THE ACTIVITY ON SUNDAY MORNING...EXPECT CHANCES TO INCREASE ON
SUNDAY AFTERNOON AND EVENING AS THE AFOREMENTIONED SHORTWAVE BEGINS
TO EXERT MORE INFLUENCE AND BETTER INSTABILITY NUDGES INTO OUR
SOUTH. WILL SEE SOME LOCALLY HEAVY RAIN POSSIBLE IN HEAVIER ACTIVITY
WITH PWAT VALUES RUNNING AROUND AN INCH AND A QUARTER. AREAS FARTHER
TO THE NORTH AND WEST WILL ACTUALLY HAVE A DECENT DAY ON SUNDAY AS
AFTERNOON TEMPERATURES MIX OUT INTO THE LOWER TO MID 70S...WHILE
AREAS AFFECTED BY CLOUD COVER/SHOWERS WILL ONLY MAKE IT UP INTO THE
MID AND UPPER 60S. BY LATE SUNDAY NIGHT THE BOUNDARY FINALLY
BEGINS TO SAG TO THE SOUTH AS THE UPPER LEVEL TROUGH PULLS TO THE
EAST...WITH AND SHOWERS AND ISOLATED THUNDERSTORMS DIMINISHING
TOWARD EARLY MONDAY MORNING. LOWS WILL REMAIN RELATIVELY
MILD...DROPPING INTO THE LOWER 40S THROUGH THE WESTERN AND CENTRAL
HIGHWAY CORRIDOR TO THE LOWER 50S THROUGH THE SIOUX CITY TO STORM
LAKE AREA.
SURFACE RIDGING THEN SLIDES ACROSS THE REGION FOR MONDAY AND TUESDAY
WITH TEMPERATURES DROPPING BACK A BIT IN A COLD AIR ADVECTION REGIME.
LOOKING AT HIGHS IN THE 60S TO NEAR 70 BOTH DAYS. IT WILL BE BREEZY
ON MONDAY WITH GOOD MIXING AND WINDS RUNNING AROUND 25 TO 30 KTS AT
THE TOP OF THE MIXED LAYER.
INTO THE EXTENDED...MORE SIGNIFICANT SYSTEM FOR THE MIDDLE OF THE
UPCOMING WEEK AS AN UPPER LEVEL TROUGH OVER THE WESTERN U.S NUDGES
EASTWARD. MODEL CONSENSUS WOULD PUT THE BULLSEYE FOR BEST
PRECIPITATION CHANCES ACROSS THE AREA IN THE WEDNESDAY NIGHT TO
THURSDAY TIMEFRAME AS THE MAIN UPPER LEVEL FORCING AND LOWER LEVEL
FRONTAL DYNAMICS COME TOGETHER. DOES APPEAR TO BE FAIRLY WINDY
THROUGH THE WEDNESDAY TO FRIDAY TIMEFRAME...WITH TEMPERATURES
TRENDING DOWNWARD BY THE END OF THE WEEK WITH THE PASSAGE OF THE
SYSTEM.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1148 PM CDT FRI APR 18 2014
THE FORECAST AREA WILL STILL SEE SOME SOUTHERLY WIND GUSTS AROUND
25 KNOTS FOR A FEW MORE HOURS...ESPECIALLY ALONG AND WEST OF
INTERSTATE 29. BUT OTHERWISE VFR CONDITIONS WILL PREVAIL FOR THE
REST OF TONIGHT THROUGH SATURDAY EVENING. DECIDED TO PUT IN A
LIGHT SHOWER FOR THE SIOUX FALLS TAF SATURDAY AFTERNOON RIGHT
ALONG A SLOW MOVING WIND SHIFT. THE WIND SHIFT WILL BE MOVING
ACROSS THE AREA ON SATURDAY...AND WILL BE ON THE DOORSTEP OF KSUX
THROUGOUT THE ENTIRE EVENING ON SATURDAY. FOR NOW...LEFT THE
CHANCES FOR LIGHT RAIN OR A THUNDERSHOWER OUT OF THE KSUX TAF THAT
FAR OUT AS CHANCES APPEAR PRETTY SKIDDISH FOR THAT AREA UNTIL
AFTER THE TAF PERIOD.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
SHORT TERM...JH
LONG TERM...JM
AVIATION...MJ
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
1115 PM MDT FRI APR 18 2014
.SHORT TERM...THIS EVENING THROUGH SATURDAY NIGHT
ISSUED AT 209 PM MDT FRI APR 18 2014
FAST FLOW OVER THE PACIFIC WILL CONTINUE TO SUPPORT FAIRLY RAPID
EASTWARD MOVEMENT OF THE SHORT WAVE TROF OVER THE PAC NW THIS
MORNING. THIS TROF WILL MOVE TO CENTRAL MT BY 00Z THIS EVENING AND
TO NEAR LAKE WG BY 12Z SAT. SHORT WAVE RIDGE AHEAD OF THIS TROF
WAS LOCATED OVER WRN SD THIS AFTERNOON...EVIDENT IN IR AND WV
SATELLITE PICS WITH COLDER AND MORE CONTINUOUS HIGH CLOUDS TO ITS
WEST AND THIN HIGH CLOUDS STREAMING OVER THE RIDGE INTO OUR CWA.
AS TROF APPROACHES...BEST SUPPORT FOR ASCENT SHOWN BY 700MB Q
VECTOR CONVERGENCE SPLITS INTO TWO AREAS. THE STRONGER MOVES
NORTHEASTWARD AHEAD OF THE TROF ACROSS ND...WHILE A SECOND AREA
DVLPS OVER SOUTHEAST WY AND ELONGATES OVER THE LOW LEVEL BAROCLINIC
ZONE OVER CO...NORTHERN NE...AND EASTERN SD BY 12Z SAT.
LOW LEVEL RESPONSE TO THESE DEVELOPMENTS ALOFT IS MODEST
CYCLOGENESIS OVER NE WY AND WESTERN SD...ONGOING THIS AFTN.
ANALYSES OF SFC GEOSTROPHIC VORTICITY CHANGES REVEAL INCREASING
VALUES OVER THIS AREA THIS AFTN. THESE CHANGES SHOULD SUPPORT
ENHANCED LOW LEVEL CONVERGENCE AND INCREASED CHANCES FOR SHOWER
AND TSTM DEVELOPMENT...THOUGH PROBABILITIES WILL REMAIN LOW. 18Z
NAM AND RECENT RUNS OF THE HRRR MODEL GIVE SUPPORT TO THIS
DEVELOPMENT...THOUGH DETAILS OF STORM LOCATION/INTENSITY HAVE BEEN
VARYING FROM RUN TO RUN OF THE HRRR.
FCST SOUNDINGS INDICATE 500 TO 750 J/KG OF CAPE OVER WRN SD LATE
THIS AFTN INTO EARLY THIS EVG. VERY LIMITED MOISTURE WILL PRECLUDE
SEVERE DEVELOPMENT...BUT INVERTED V SOUNDINGS WITH HIGH LCLS
SUGGEST POTENTIAL FOR A FEW STRONG WIND GUSTS WITH ANY STORMS THAT
DO DEVELOP.
FOLLOWING PASSAGE OF THE COLD FRONT AND NORTH EASTWARD MOVEMENT OF
THE SFC LOW...BRISK NORTHWESTERLY WINDS WILL DEVELOP OVER THE
WHOLE CWA LATE TONIGHT INTO EARLY SAT MORNING WITH COOLER
TEMPERATURES AND DRY WEATHER ON SATURDAY AND SATURDAY NIGHT.
&&
.LONG TERM...SUNDAY THROUGH FRIDAY
ISSUED AT 209 PM MDT FRI APR 18 2014
THE UPPER LEVEL THERMAL RIDGE WILL SHIFT OFF TO THE
EAST SUNDAY AFTN AS AN UPPER TROUGH CROSSES NORTH DAKOTA AND SWINGS
A COOL FRONT ACROSS THE FORECAST AREA. WEAK INSTABILITY DEVELOPS
OVER WESTERN SOUTH DAKOTA AHEAD OF THE FRONT ON SUNDAY AFTERNOON.
HOWEVER DUE TO THE LOW RH OF THE AIRMASS IN PLACE AT THE TIME WILL
LEAVE THE SUN AFTN FORECAST DRY. THE UPPER RIDGE WILL REBOUND
QUICKLY OVER THE NORTHERN PLAINS ON MONDAY WITH WARM AND DRY WEATHER
CONTINUING THROUGH TUESDAY. A STRONG AND SLOW MOVING UPPER LEVEL
TROUGH WILL CREATE CHANCES OF PRECIPITATION FROM TUESDAY NIGHT INTO
FRIDAY. SHRA/TSRA WILL BE POSSIBLE...ESPECIALLY TUESDAY/WEDNESDAY.
MODELS REMAIN IN DECENT AGREEMENT IN PUSHING THE MAIN UPPER
LOW/SHORTWAVE ASSOCIATED WITH UPPER TROUGH NORTH OF CWA...WHICH
WOULD RESULT IN A MOSTLY LIQUID EVENT. CAN/T RULE OUT SOME SLUSHY
SNOW THURSDAY NIGHT...BUT MOISTURE AVAILABILITY BEHIND SYSTEM IN
QUESTION.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1049 PM MDT FRI APR 18 2014
GUSTY NORTHWESTERLY WINDS ARE EXPECTED BEHIND A COLD
FRONT THROUGH EARLY MORNING...ESP ACROSS THE NW SOUTH DAKOTA
PLAINS AND IN THE LEE OF THE BLACK HILLS. VFR CONDITIONS WILL
PREVAIL ACROSS MOST OF THE FA THROUGH THE PERIOD...SAVE FOR A
PATCH OF MVFR CIGS ACROSS NE WY AND FAR NW SD EARLY THIS MORNING.
&&
.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&
$$
SHORT TERM...BARBER
LONG TERM...10
AVIATION...JC
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
624 PM CDT SUN APR 20 2014
.AVIATION...
UPPER LOW MOVING ACROSS THE PANHANDLE ATTM WITH SCATTERED SHOWERS
AND ISOLATED THUNDER UNDERNEATH IT. CONVECTION SHOULD SHIFT TO THE
EAST OF THE AREA BY 03Z. THREAT OF THUNDER AT EITHER TERMINAL IS
NON-ZERO BUT NOT BIG ENOUGH TO RUN WITH A PREVAILING OR TEMPO
GROUP ATTM. VFR CONDITIONS LIKELY THROUGH THE NIGHT WITH SMALL
CHANCE FOR SOME FOG AND/OR LOW CLOUDS AHEAD OF A COLD FRONT TOWARD
12Z...AGAIN THE CHANCE OF WHICH IS TOO SMALL TO INSERT MENTION
INTO EITHER TAF. FINALLY...WIND SWITCH TO NORTH WITH THE COLD
FRONT MONDAY MORNING.
&&
.PREV DISCUSSION... /ISSUED 337 PM CDT SUN APR 20 2014/
SHORT TERM...
VIS SAT SHOWS A LINE OF CU DEVELOPING IN THE WESTERN TX PANHANDLE
AND IS GRADUALLY PUSHING EASTWARD WHILE DEVELOPING SOUTHWARD. A FEW
RETURNS HAVE SHOWED UP ON RADAR OVER PARMER COUNTY WHICH IS RIGHT IN
LINE WITH THIS CU DEVELOPMENT. THIS IS MOST LIKELY ASSOCIATED WITH
THE /DRY/ LINE AS SURFACE OBS INDICATE A SURFACE TROF IN THE
AFOREMENTIONED AREA WITH WESTERLY WINDS AND SLIGHTLY DRIER DEWPOINTS
MOVING IN BEHIND THE TROF. THE DRY LINE WILL CONTINUE WITH ITS
EAST/SOUTHEASTWARD MOVEMENT AS THE UPPER LEVEL LOW TO OUR NORTHWEST
MOVES CLOSER. CURRENT RAP ANALYSIS INDICATES THAT COLDER AIR ALOFT
IS PUSHING IN AND IS INCREASING OUR LAPSE RATES. SCATTERED SKIES ARE
HELPING AID SOME SURFACE HEATING IN TURN HELPING TO SLOWLY ERODE
WHAT CAP IS LEFT. AS CLEARER SKIES MOVE EASTWARD THIS SHOULD HELP
WARM THE SURFACE MORE TO THE POINT OF FULL CAP EROSION. THIS WILL
HELP FIRE CONVECTION MORE QUICKLY AS THE DRYLINE MOVES INTO THE
CENTRAL SOUTH PLAINS AND TX PANHANDLE. FORECAST SOUNDINGS CONTINUE
TO INDICATE THE POTENTIAL FOR STRONG TO SVR CONVECTION WITH CHANCES
INCREASING THROUGH THE AFTERNOON/EVENING EASTWARD. WHILE CAPE THERMO
PROFILES ARE ADEQUATE TO PRODUCE SVR HAIL AND WINDS...0-6KM SHEAR IS
HIGH END MARGINAL TOPPING OUT AT AROUND 40 KTS OVER THE ROLLING
PLAINS AND 35 KTS ALONG THE I27/HWY84 CORRIDOR. I HAVE KEPT
INHERITED POPS BEFORE 00Z WITH SVR MENTION AND INCREASED COVERAGE TO
50 POPS OVER THE ROLLING PLAINS FOR LATER TONIGHT.
PRECIP/CONVECTION CHANCES WILL QUICKLY DIMINISH AS THE DRY
LINE/UPPER LEVEL LOW MOVES EASTWARD AND AS A WEAK FRONT PUSHING INTO
THE AREA TOMORROW MORNING. TEMPS WILL BE WARM IN THE MID 70S TO 80S
TOMORROW AS CAA WILL BE WEAK AND SHORT LIVED DURING THE MORNING AND
SKIES WILL CLEAR MAKING WAY FOR SOLAR HEATING. ALDRICH
LONG TERM...
LITTLE CHANGE FOR THE EXTENDED PORTION OF THE FORECAST THIS GO AROUND.
WE CONTINUE TO LOOK FOR WARMER TEMPS AND A RETURN TO SOUTH BREEZES
TUESDAY AS SHORTWAVE RIDGE BRIEFLY TRANSITS WTX DOWNSTREAM OF A
FAIRLY DEEP TROUGH MOVING ACROSS THE WEST. FAIRLY ROBUST MOISTURE
RETURN IS EXPECTED TUESDAY NIGHT ON THE NOSE OF THE LLJ. THE GFS AND
ECMWF REMAIN IN DECENT AGREEMENT THAT AS THE SHORTWAVE TROUGH
CROSSES THE ROCKIES...A DRYLINE SHOULD DEVELOP ACROSS THE SRN
PLAINS. MODELS ARE STILL IN FLUX WITH THE EAST-WEST POSITION OF
THE DRYLINE BY PEAK HEATING...BUT IT APPEARS LIKELY IT WILL BE
SOMEWHERE IN THE VICINITY OF THE CAPROCK ESCARPMENT. WE CONTINUE
TO CARRY A SLIGHT CHANCE OF TSTMS TO THE EAST OF THE DRYLINE...AND
HAVE BUMPED POPS UP SLIGHTLY INTO THE CHANCE CATEGORY ACROSS THE
NE ZONES. A WEAK COLD FRONT WILL FOLLOW ON THURSDAY...ALTHOUGH IT
MAY NOT PASS THROUGH THE ENTIRE CWA BEFORE LIFTING. ANOTHER LARGE
TROUGH WILL FOLLOW FOR NEXT WEEKEND...ALTHOUGH THERE CONTINUES TO
BE A LOT OF UNCERTAINTY REGARDING THE STRENGTH AND ORIENTATION OF
THE MID-LVL FLOW ACROSS THE SRN PLAINS AND WHETHER OR NOT WE CAN
HOLD ON TO LOW-LVL MOISTURE. DRYLINE ACTIVITY MAY BE POSSIBLE SAT
AND SUN ACROSS ERN ZONES...BUT HAVE MAINTAINED POPS BELOW MENTION
FOR NOW. AFTER A BRIEF COOL DOWN MOST AREAS ON THURSDAY....TEMPS
SHOULD BE A LITTLE ABOVE NORMAL HEADING INTO THE WEEKEND.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 50 74 51 79 52 / 10 10 0 0 0
TULIA 51 76 50 80 55 / 30 10 0 0 0
PLAINVIEW 53 78 51 81 56 / 20 10 0 0 0
LEVELLAND 54 80 54 82 59 / 10 10 0 0 0
LUBBOCK 55 81 56 81 60 / 20 10 0 0 0
DENVER CITY 55 78 55 82 61 / 10 10 0 0 0
BROWNFIELD 54 79 56 83 60 / 10 10 0 0 0
CHILDRESS 58 82 56 82 57 / 50 10 0 0 0
SPUR 58 83 57 82 60 / 40 10 0 0 0
ASPERMONT 60 85 58 83 61 / 40 10 0 0 0
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
07
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
341 PM CDT SAT APR 19 2014
.SHORT TERM...
WV IMAGERY SHOWS OUR UPPER LOW OF INTEREST CONTINUING TO SLOWLY MOVE
EASTWARD WHILE CONTINUING TO DRAW IN TROPICAL MOISTURE FROM THE
PACIFIC. A SHORTWAVE PUSHING NORTH AND EASTWARD IS ALSO VISIBLE ON
WV AND HAS BECOME MORE PRONOUNCED OVER THE PAST SEVERAL HOURS. THE
SHORTWAVE STRETCHES FROM SOUTHERN NM THROUGH THE PERMIAN BASIN TO
THE EDWARDS PLATEAU AND IS AIDING IN THE NUMEROUS SHOWER ACTIVITY IN
SOUTHEAST NM AND ALONG THE TX/NM STATE LINE. SHOWERS HAVE BEEN SLOW
TO MOVE EASTWARD IN PART DUE TO DRY AIR IN THE MID LEVELS. MUCH OF
THE RAIN THAT HAS FALLEN HAS BEEN MOSTLY VIRGA WITH SOME LIGHT RAIN
MAKING ITS WAY TO THE GROUND. LOOKING AT TRENDS FROM RAP ANALYSIS
TOP DOWN MOISTENING IS HAPPENING BUT NOT IN AN EXTREME HURRY. WE
SHOULD BE ABLE TO MOISTEN UP ENOUGH FOR WHEN THE SHORTWAVE MOVES
OVERHEAD LATER THIS AFTERNOON INTO THE EVENING WHICH SHOULD PROVIDE
NUMEROUS SHOWERS. I HAVE INCREASED POPS TO AROUND 60 FOR THE WESTERN
HALF OF THE FA BUT HAVE CHANGED THE WX CATEGORY TO RAIN SHOWERS WITH
A MENTION OF ISO THUNDER AS LAPSE RATES WILL BE SLOW TO STEEPEN AS
THE CENTER OF THE LOW WILL STILL BE WELL TO OUR WEST. THIS ALONG
WITH CLOUDY SKIES FOR A MAJORITY OF THE DAY HAVE LIMITED DAYTIME
HEATING AND HAVE KEPT TEMPS ON THE COOL SIDE.
RAIN SHOWERS AND THUNDERSTORMS WILL PERSIST THROUGH THE LATE EVENING
AND ACTIVITY SHOULD TAPER DOWN AFTER MIDNIGHT WHEN THE SHORTWAVE HAS
PASSED TO THE NORTH. THE NEXT FOCUS WILL BE TOMORROW AFTERNOON AND
EVENING AS THE UPPER LEVEL LOW OPENS AND THE TROF MOVES INTO THE
AREA. MODELS HAVE DIFFERED SLIGHTLY ON HOW TO HANDLE IT BUT AGREE IN
DRYLINE CONVECTION FIRING LATE TOMORROW AFTERNOON. THE MAIN
DIFFERENCE IN MODELS IS HOW FAR WEST WILL THE DRYLINE BEGIN TO
CONVECT. THE NAM/TTU WRF SHOW THE DRYLINE CONVECTING IN THE
SOUTHWESTERN TX PANHANDLE AND PUSHES SOUTHEASTWARD WHILE THE GFS
FIRES CONVECTION NEAR THE EDGE OF THE CAPROCK AND PUSHES EASTWARD.
FOR NOW I HAVE CONTINUED TO OPT FOR A BIT FARTHER WEST AS LOW LEVEL
MOISTURE WILL STILL BE AVAILABLE AND THIS SCENARIO HAS BEEN MORE
CONSISTENT WITH THE NAM/TTU WRF. CONCERNING SEVERE POTENTIAL...MID
LEVEL LAPS RATES WILL STEEPEN AS THE TROF AXIS MOVES OVERHEAD WHICH
WILL INCREASE OVERALL CAPE...BUT THE AMOUNT OF SBCAPE IS IN QUESTION
AS THE SUN WILL STRUGGLE TO PEAK THROUGH THE CLOUDS TOMORROW. THERE
MAY BE A WINDOW OF OPPORTUNITY TOMORROW FOR THE SUN TO SHINE THROUGH
HELPING TO WARM SURFACE TEMPS. MUCAPE AROUND 1000 J/KG WILL BE
ENOUGH TO TRIGGER STRONG CONVECTION ALONG THE DRYLINE. 0-6KM SHEAR
AROUND 35 TO 45 KTS WITH MARGINAL DRY AIR ALOFT WILL HELP AID IN
HAIL GROWTH PRODUCING LOW END SEVERE HAIL. SOME STRONG WINDS
REACHING SEVERE CRITERIA WILL BE POSSIBLE AS WELL...HOWEVER
WIDESPREAD SEVERE THUNDERSTORMS ARE NOT ANTICIPATED ATM AND WILL BE
ISOLATED IN NATURE. ALDRICH
&&
.LONG TERM...
THE SLOW-MOVING UPPER TROUGH WILL BE SLOWLY EXITING THE AREA
SUNDAY EVENING. INDICATIONS ARE THAT THE ATMOSPHERE WILL BE FAIRLY
WORKED OVER BY EVENING AND WITH DECREASING SFC-BASED
INSTABILITY...ANY SEVERE THREAT SHOULD DIMINISH AFTER 8 PM OR SO.
SHOWERS MAY CONTINUE ACROSS THE EASTERN AREAS INTO THE NIGHT
THOUGH...GRADUALLY DECREASING IN COVERAGE AND STRENGTH FROM WEST
TO EAST. NW FLOW IN THE WAKE OF THE TROUGH WILL OPEN THE DOOR FOR
A WEAK FRONT TO MOVE SOUTH ACROSS THE AREA MONDAY. THERE IS SOME
SUGGESTION OF SOME LIGHT SHOWERS ACROSS OUR ERN ZONES AND ALSO
PERHAPS IN THE NW...BUT WE/VE KEPT POPS BELOW MENTION FOR NOW. NOT
MUCH CHANGE IN THE FORECAST BEYOND MONDAY. SHORTWAVE RIDGING ON
TUESDAY SHOULD BRING WARMER TEMPS WHILE WINDS WILL RETURN TO A SERLY
FETCH. FAIRLY DEEP TROUGH MOVING INTO THE ROCKIES SHOULD INDUCE A
NICE LLJ TUESDAY NIGHT...AND BEGIN TO ADVECT GULF MOISTURE BACK
INTO WTX. THE GFS STILL IS PRETTY BULLISH WITH THE MOISTURE RETURN
ALL THE WAY TO THE STATE LINE OVERNIGHT AND COULD LIKELY RESULT IN
SOME MORNING LOW STRATUS ACROSS THE CWA WEDNESDAY. THE LATEST GFS
AND ECMWF REMAIN IN PRETTY GOOD AGREEMENT THAT A DRYLINE WILL FORM
SOMEWHERE ACROSS THE EASTERN HALF OF THE CWA AND BOTH CONTINUE TO
SHOW A GOOD QPF SIGNAL TO THE EAST OF THE DRYLINE WED AFTERNOON
AND EVENING. THERE IS A BIT OF A CONCERN WITH THE STRENGTH OF THE
CAP OVER THE DRYLINE...GUIDANCE IS CURRENTLY PROGGING TEMPS ONLY
IN THE LOWER/MIDDLE 80S WHICH MAY NOT BE SUFFICIENT TO BREAK THIS
CAP. WE ARE FORECASTING SOMEWHAT WARMER TEMPS BASED ON THE
PATTERN...AND WE HAVE KEPT A SLIGHT CHANCE OF TSTMS EAST OF THE
DRYLINE. DRIER AIR SHOULD SPREAD ACROSS THE AREA ON THURSDAY WITH
ANOTHER WEAK FROPA LIKELY LATE THURSDAY OR FRIDAY. QUITE A BIT OF
UNCERTAINTY IN THE FORECAST HEADING INTO NEXT WEEKEND. ANOTHER
FAIRLY DEEP TROUGH WILL FORM UP ACROSS THE WEST...BUT MODELS
DIVERGE WITH THE ECMWF SHOWING VEERED BROAD CYCLONIC FLOW OVER WTX
SHUNTING DEEP MOISTURE TO THE EAST...WHILE THE GFS SHOWS LESS OF A
WESTERLY COMPONENT AND A BETTER CHANCE OF MOISTURE HOLDING IN AND
POSSIBLY LEADING TO SOME PRECIP POTENTIAL. WE/LL KEEP THE DRY FCST
RUNNING WHILE FOLLOWING THE TRENDS.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 50 74 49 77 49 / 60 20 10 10 0
TULIA 54 75 52 78 51 / 30 30 20 10 0
PLAINVIEW 54 75 54 80 52 / 40 30 20 10 0
LEVELLAND 54 76 54 80 52 / 60 20 10 10 0
LUBBOCK 57 77 55 81 53 / 60 30 20 10 0
DENVER CITY 55 78 55 79 53 / 60 20 10 10 0
BROWNFIELD 56 78 54 80 53 / 60 20 10 10 0
CHILDRESS 58 80 58 82 55 / 30 40 30 10 10
SPUR 57 79 59 84 55 / 30 40 20 10 0
ASPERMONT 58 79 60 85 56 / 30 40 30 10 0
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
51/33
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1251 PM EDT SAT APR 19 2014
.SYNOPSIS...
A DEEP AREA OF LOW PRESSURE ALOFT ACROSS THE SOUTHEAST STATES WILL
MOVE VERY SLOWLY EASTWARD THROUGH THE WEEKEND...MOVING OFF THE
COAST BY MONDAY...KEEPING CLOUDS AND LIGHT RAIN ACROSS SOUTHERN
SECTIONS TODAY INTO EARLY SUNDAY. HIGH PRESSURE WILL BUILD ACROSS
THE REGION FOR LATER SUNDAY INTO MONDAY. BY TUESDAY...A COLD FRONT
AND ASSOCIATED UPPER TROUGH WILL MOVE INTO THE REGION FROM THE
NORTHWEST BRINGING A CHANCE FOR SHOWERS AND THUNDERSTORMS...FOLLOWED
BY BREEZY AND COOLER CONDITIONS FOR THE MID PART OF NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1155 AM EDT SATURDAY...
UPDATED TO RAISE HIGH TEMPS ANOTHER CAT OR TWO ESPCLY NORTH/EAST
GIVEN MORE BREAKS AND THINNING OF CLDNS ONGOING NORTH OF THE
PERSISTENT RAINBAND ACROSS NW NC. THIS WILL RESULT IN A GRADIENT
BETWEEN MID/UPPER 60S NORTH TO PERHAPS ONLY AROUND 50 FAR SW WHERE
CLOUDS/PRECIP WILL CONTINUE. ALSO LOWERED POPS IN SOUTHERN VA TO
REFLECT DECREASE IN COVERAGE DURING THE PAST HOUR OR TWO WHILE
MAINTAINING CAT POPS WATAUGA/WIKLES AND YADKIN CTYS.
AS OF 930 AM EDT SATURDAY...
ELONGATED BAND OF RAIN ASSOCIATED WITH THE MID LEVEL DEFORMATION
ZONE OF THE BROAD UPPER LOW ACROSS NORTH FLORIDA REMAINS ACROSS
THE FAR SOUTHERN TIER THIS MORNING. HOWEVER LATEST MORNING
SOUNDINGS CONTINUE TO SHOW A STRONG NE FLUX OF DRIER AIR IN THE
LOWER LEVELS AS EVIDENCED VIA THE RNK RAOB. THIS HAS CAUSED SOME
DRYING TO TAKE PLACE ALONG THE BLUE RIDGE SOUTH TO NEAR THE
VIRGINIA BORDER WHICH IS CLOSER TO THE LATEST HRRR SOLN THAT
ATTEMPTS TO SHIFT ALL THE PRECIP SOUTH THIS AFTERNOON. GFS
CONTINUES TO MAINTAIN THE AXIS OF LIGHT RAIN WITH MORE EASTERLY
INFLOW OFF THE ATLANTIC AS THE UPPER SYSTEM ONLY DRIFTS TO OFF THE
SE COAST BY THIS EVENING. THIS SCENARIO APPEARS MORE IN LINE WITH
A SHARP GRADIENT FROM SOME SUN NORTH...TO CLOUDS CENTRAL
SECTIONS...WITH CONTINUED PERIODS OF -RA VA/NC BORDER AND POINTS
SOUTH AS THE BAND TENDS TO STRETCH OUT WHILE SLOWLY DIMINISHING
THROUGH THE AFTERNOON. THIS SUPPORTS KEEPING CAT/LIKELY POPS A
WHILE LONGER ACROSS MUCH OF NW NC INTO SOUTHSIDE VIRGINIA WITH A
QUICK DROPOFF TO DRY CONDITIONS FROM JUST SOUTH OF HIWAY 460 AND
POINTS NORTH.
HIGH TEMPS REMAIN TRICKY WITH POTENTIAL FOR HIGHS TO STRUGGLE TO
TOP 50 UNDER THE RAIN WHILE REACHING THE LOW/MID 60S FAR
NORTH/WEST WITH 56-63 BCB-ROA-LYH CORRIDOR PENDING DEGREE OF ANY
BREAKS. THUS INCREASED THE GRADIENT THIS AFTERNOON SINCE ALREADY
ABOVE HIGHS IN SPOTS NORTH OF THE MAIN RAIN/CLOUD SHIELD ATTM.
PREVIOUS DISCUSSION...
MAIN CONCERN THROUGH THE NEAR TERM CONTINUES TO BE SLOW
MOVING...INCREASINGLY VERTICALLY STACKED UPPER LOW ACROSS THE
SOUTHEAST STATES. FINALLY...AFTER SEVERAL DAYS OF DIFFERING
SOLUTIONS AMONG THE MODELS...THE GFS/ECMWF/NAM/CANADIAN HAVE ALL
CONVERGED ON A SIMILAR SOLUTION. EXPECT -RA TO GENERALLY REMAIN IN
AN AREA THROUGH THIS EVENING SIMILAR TO WHERE IT IS...NAMELY
MOSTLY ALONG AND EAST OF THE BLUE RIDGE FROM TNB-HLX-LYH. WITH THE
UPPER LOW MOVING ALMOST DUE EAST THROUGH THE PERIOD...SEE LITTLE
NORTHWARD PROGRESS OF THE RAIN FROM THESE POINTS...BUT BY THE SAME
TOKEN...LITTLE SOUTHWARD PROGRESS UNTIL THE UPPER LOW MOVES CLOSER
TO THE COAST...ALLOWING DRIER NE FLOW TO ADVECT SOUTHWARD INTO THE
REGION. FOR AREAS FURTHER NORTH AND WEST...CONSIDERABLE HIGH
CLOUDS WILL PERSIST AND EVEN SOME MID CLOUDS ARE EXPECTED TO REACH
THE ALLEGHANY FRONT...BUT LITTLE TO NO PRECIPITATION WEST OF THE
BLUE RIDGE. GFS/ECMWF BOTH CLEARLY DEPICT A SMALL DEFORMATION ZONE
TO DEVELOP ACROSS NORTHWEST NC THIS EVENING...PROLONGING THE
PRECIPITATION IN THAT AREA. HAVE INCREASED POPS TO LIKELY AND
CATEGORICAL AND EXTENDED LONGER INTO OUR SOUTHERN TIER OF COUNTIES
THAN EARLIER ADVERTISED.
SYNOPTIC PATTERN AND -RA...SOME WHAT OF AN INSITU WEDGE REINFORCED
WITH NE FLOW AROUND SE U.S. DEVELOPING SFC LOW PRESSURE...WILL
KEEP THE PIEDMONT THE COOLEST TODAY. HAVE LEANED TOWARD THE ECMWF
MOS...WHICH WAS THE COOLEST AMONG THE MAV/MET/ECS. HOWEVER...EVEN
UNDERCUT IT BY ABOUT ONE CATEGORY IN THE RAINY PIEDMONT AREAS. THE
MOUNTAINS OF NORTHWEST NC WILL STRUGGLE TO REACH 50. THE WARMEST
AREAS TODAY SHOULD BE WEST OF THE ALLEGHANY FRONT...LWB-BLF-
MKJ...WHERE LOW 60S ARE POSSIBLE IF THE CLOUDS THIN OUT ENOUGH
DURING THE MID AND LATE AFTERNOON.
WINDS WILL REMAIN NE EAST OF THE ALLEGHANY FRONT AND GENERALLY
E-SE TO THE WEST. SPEEDS WILL INCREASE DURING THE AFTERNOON AND
EVENING AS A TIGHT PRESSURE GRADIENT DEVELOPS BETWEEN THE LOW
PRESSURE ACROSS SC AND HIGH PRESSURE RIDGING SOUTHWARD FROM NEW
ENGLAND.
&&
.SHORT TERM /SUNDAY THROUGH TUESDAY NIGHT/...
AS OF 400 AM EDT SATURDAY...
FOR EASTER SUNDAY...MAY SEE A FEW RESIDUAL SPRINKLES ACROSS THE
SOUTHSIDE AND THE NORTH CAROLINA PIEDMONT TO START THE DAY...HOWEVER
THESE WILL QUICKLY EXIT THE AREA AS LOW PRESSURE EXITS OFF THE
SOUTHEAST COAST. OTHERWISE...EXPECT CLEARING SKIES AS HIGH PRESSURE
REMAINS WEDGED AGAINST THE EASTERN FACE OF THE APPALACHIANS...
RESULTING IN A LIGHT AND GENERALLY EASTERLY WIND FLOW. WITH THE COOL
HIGH PRESSURE WEDGE IN PLACE...WENT A LITTLE BELOW MODEL GUIDANCE
FOR AFTERNOON TEMPERATURES...WITH HIGHS CLIMBING INTO THE MID AND
UPPER 60S MOST LOCATIONS OUTSIDE OF THE HIGHER RIDGES. LIGHT WINDS
AND MOSTLY CLEAR SKIES WILL ALLOW FOR STRONG RADIATIONAL COOLING
SUNDAY NIGHT...WITH LOWS BOTTOMING OUT IN THE UPPER 30S AND LOW
40S...WITH A FEW MOUNTAIN VALLEYS DROPPING BELOW FREEZING.
UPPER LEVEL RIDGING BECOMES MORE FIRMLY ESTABLISHED FOR MONDAY AS
THE SURFACE HIGH PRESSURE WEDGE SHOWS SIGNS OF BREAKING DOWN.
EXPECT WARMER TEMPERATURES DESPITE INCREASING MID AND HIGH
CLOUDS...WITH HIGHS REACHING INTO THE UPPER 60S AND LOW 70S. WINDS
WILL BECOME INCREASINGLY SOUTHWESTERLY THROUGH THE DAY AHEAD OF AN
APPROACHING COLD FRONT...AND THE WARMER AIR POOLING IN FROM THE
GULF COAST REGION WILL MAKE FOR MILD MONDAY NIGHT LOWS...GENERALLY
IN THE UPPER 40S AND LOW 50S.
SHOWER ACTIVITY WILL ENTER FROM THE WEST AFTER SUNRISE TUESDAY AS
THE COLD FRONT ADVANCES EAST ACROSS KENTUCKY/TENNESSEE. GFS/ECMWF/
CANADIAN FORECAST MODELS ALL INDICATE DECENT INSTABILITY DEVELOPING
DURING THE AFTERNOON ALONG AND EAST OF THE BLUE RIDGE AS A LEE SIDE
TROUGH SETS UP...WHILE STRONG HEATING WILL ALLOW TEMPERATURES TO
CLIMB INTO THE MID AND UPPER 70S. AS SUCH...CONDITIONS APPEAR
FAVORABLE FOR SCATTERED THUNDERSTORMS TO DEVELOP...A FEW OF WHICH
WILL LIKELY BECOME STRONG TO SEVERE. AT THIS POINT...BOTH HAIL AND
GUSTY WINDS WOULD BE CONCERNS. THE COLD FRONT WILL PASS ACROSS THE
AREA DURING THE EVENING...EXITING TO THE EAST AFTER MIDNIGHT
WEDNESDAY. A FEW UPSLOPE RAIN SHOWERS MAY LINGER ACROSS THE WESTERN
RIDGES THROUGH THE NIGHT...OTHERWISE CLEARING CONDITIONS ARE
EXPECTED.
&&
.LONG TERM /WEDNESDAY THROUGH FRIDAY/...
AS OF 400 AM EDT FRIDAY...
BELIEVE THERE WILL STILL BE A CHANCE FOR SOME UPSLOPE RAIN SHOWERS
IN CAA WEST OF THE BLUE RIDGE EARLY WEDNESDAY...IN ADDITION TO
BREEZY CONDITIONS AS HIGH PRESSURE BUILDS IN FROM THE NORTHWEST.
EXPECT QUIET WEATHER FOR THURSDAY AS HIGH PRESSURE PASSES OVERHEAD.
SHOWERS AND POSSIBLE THUNDERSTORMS WILL MOVE IN ON FRIDAY AS ANOTHER
COLD FRONT APPROACHES.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
AS OF 1230 PM EDT SATURDAY...
DRIER LOW LEVEL NE FLOW HAS CONTINUED TO MAINTAIN VFR STATUS AT
ALL TAF SITES ATTM WITH MOSTLY A MID TO HIGH BKN/OVC CANOPY IN
PLACE. EXPECT THIS OVERALL TREND TO PREVAIL THIS AFTERNOON WITH
MOST OF THE MVFR CONDITIONS STAYING ALONG THE SRN BLUE RIDGE IN NW
NORTH CAROLINA AND JUST SOUTH OF DAN. MAY SEE SOME LOW END VFR
CIGS DEVELOP NORTH INTO DAN BEFORE THIS EVENING AS MOISTURE/PRECIP
STARTS TO JOG BACK NORTH AHEAD OF ANOTHER WAVE SET TO MOVE ACROSS
OVERNIGHT. COULD ALSO BE SOME SPOTTY -RA ACROSS THE DAN VICINITY
AS WELL BUT OVERALL VFR WITH DRY WEATHER ELSW THIS AFTERNOON.
LOW CONFIDENCE FORECAST OVERNIGHT WITH SOME GUIDANCE SUGGESTING
THE NEXT MID LEVEL WAVE MAY BRING PRECIP BACK NORTH AT LEAST INTO
DAN THIS EVENING BEFORE EXITING EARLY SUNDAY. THIS WOULD ALSO
BRING A PERIOD OF MVFR CIGS ALONG WITH VFR CIGS NORTH TO ROA/LYH
OVERNIGHT. SINCE THIS COULD BE OVERDONE GIVEN CURRENT DRY
ADVECTION AND LACK OF MODEL CONSENSUS...WILL KEEP DAN HIGH END
MVFR CIGS WITH VFR VSBYS IN -RA LATER TONIGHT...AND MAINLY SCTD
LOW CLOUDS WITH HIGHER MID DECK CIGS ELSW FROM BCB-ROA-LYH FOR
NOW.
NE WINDS WILL REMAIN GUSTY ESPCLY OVER EASTERN SECTIONS WITH THE
PRESSURE GRADIENT IN PLACE BRINGING GUSTS TO 20-25 KTS AT TIMES
INTO TONIGHT.
EXTENDED AVIATION DISCUSSION...
THE UPPER LOW SLOWLY EXITS TO THE EAST SUNDAY AND HIGH PRESSURE
RETURNS BRINGING A RETURN TO VFR CONDITIONS INTO EARLY NEXT WEEK.
MAY STILL HAVE SOME MID DECK CIGS ACROSS THE EAST SUNDAY MORNING
BEFORE SLOW CLEARING TAKES PLACE FROM WEST TO EAST BY AFTERNOON. THE
NEXT COLD FRONT APPROACHES MONDAY NIGHT WITH MORE SHOWERS AND
POSSIBLE THUNDERSTORMS INCLUDING PERIODS OF MVFR FOR TUESDAY.
FRONT EXITS TUESDAY NIGHT RESULTING IN A RETURN TO VFR WEDNESDAY
EXCEPT FOR MVFR CIGS OVER THE FAR WESTERN SITES IN SE WEST VA.
HIGH PRESSURE BUILDS IN FOR THURSDAY WITH WIDESPREAD VFR LIKELY.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...RAB
NEAR TERM...JH/RAB
SHORT TERM...NF
LONG TERM...MBS/NF
AVIATION...JH/RAB/RCS
AREA FORECAST DISCUSSION...UPDATED
NWS BLACKSBURG VA
1204 PM EDT SAT APR 19 2014
.SYNOPSIS...
A DEEP AREA OF LOW PRESSURE ALOFT ACROSS THE SOUTHEAST STATES WILL
MOVE VERY SLOWLY EASTWARD THROUGH THE WEEKEND...MOVING OFF THE
COAST BY MONDAY...KEEPING CLOUDS AND LIGHT RAIN ACROSS SOUTHERN
SECTIONS TODAY INTO EARLY SUNDAY. HIGH PRESSURE WILL BUILD ACROSS
THE REGION FOR LATER SUNDAY INTO MONDAY. BY TUESDAY...A COLD FRONT
AND ASSOCIATED UPPER TROUGH WILL MOVE INTO THE REGION FROM THE
NORTHWEST BRINGING A CHANCE FOR SHOWERS AND THUNDERSTORMS...FOLLOWED
BY BREEZY AND COOLER CONDITIONS FOR THE MID PART OF NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1155 AM EDT SATURDAY...
UPDATED TO RAISE HIGH TEMPS ANOTHER CAT OR TWO ESPCLY NORTH/EAST
GIVEN MORE BREAKS AND THINNING OF CLDNS ONGOING NORTH OF THE
PERSISTENT RAINBAND ACROSS NW NC. THIS WILL RESULT IN A GRADIENT
BETWEEN MID/UPPER 60S NORTH TO PERHAPS ONLY AROUND 50 FAR SW WHERE
CLOUDS/PRECIP WILL CONTINUE. ALSO LOWERED POPS IN SOUTHERN VA TO
REFLECT DECREASE IN COVERAGE DURING THE PAST HOUR OR TWO WHILE
MAINTAINING CAT POPS WATAUGA/WIKLES AND YADKIN CTYS.
AS OF 930 AM EDT SATURDAY...
ELONGATED BAND OF RAIN ASSOCIATED WITH THE MID LEVEL DEFORMATION
ZONE OF THE BROAD UPPER LOW ACROSS NORTH FLORIDA REMAINS ACROSS
THE FAR SOUTHERN TIER THIS MORNING. HOWEVER LATEST MORNING
SOUNDINGS CONTINUE TO SHOW A STRONG NE FLUX OF DRIER AIR IN THE
LOWER LEVELS AS EVIDENCED VIA THE RNK RAOB. THIS HAS CAUSED SOME
DRYING TO TAKE PLACE ALONG THE BLUE RIDGE SOUTH TO NEAR THE
VIRGINIA BORDER WHICH IS CLOSER TO THE LATEST HRRR SOLN THAT
ATTEMPTS TO SHIFT ALL THE PRECIP SOUTH THIS AFTERNOON. GFS
CONTINUES TO MAINTAIN THE AXIS OF LIGHT RAIN WITH MORE EASTERLY
INFLOW OFF THE ATLANTIC AS THE UPPER SYSTEM ONLY DRIFTS TO OFF THE
SE COAST BY THIS EVENING. THIS SCENARIO APPEARS MORE IN LINE WITH
A SHARP GRADIENT FROM SOME SUN NORTH...TO CLOUDS CENTRAL
SECTIONS...WITH CONTINUED PERIODS OF -RA VA/NC BORDER AND POINTS
SOUTH AS THE BAND TENDS TO STRETCH OUT WHILE SLOWLY DIMINISHING
THROUGH THE AFTERNOON. THIS SUPPORTS KEEPING CAT/LIKELY POPS A
WHILE LONGER ACROSS MUCH OF NW NC INTO SOUTHSIDE VIRGINIA WITH A
QUICK DROPOFF TO DRY CONDITIONS FROM JUST SOUTH OF HIWAY 460 AND
POINTS NORTH.
HIGH TEMPS REMAIN TRICKY WITH POTENTIAL FOR HIGHS TO STRUGGLE TO
TOP 50 UNDER THE RAIN WHILE REACHING THE LOW/MID 60S FAR
NORTH/WEST WITH 56-63 BCB-ROA-LYH CORRIDOR PENDING DEGREE OF ANY
BREAKS. THUS INCREASED THE GRADIENT THIS AFTERNOON SINCE ALREADY
ABOVE HIGHS IN SPOTS NORTH OF THE MAIN RAIN/CLOUD SHIELD ATTM.
PREVIOUS DISCUSSION...
MAIN CONCERN THROUGH THE NEAR TERM CONTINUES TO BE SLOW
MOVING...INCREASINGLY VERTICALLY STACKED UPPER LOW ACROSS THE
SOUTHEAST STATES. FINALLY...AFTER SEVERAL DAYS OF DIFFERING
SOLUTIONS AMONG THE MODELS...THE GFS/ECMWF/NAM/CANADIAN HAVE ALL
CONVERGED ON A SIMILAR SOLUTION. EXPECT -RA TO GENERALLY REMAIN IN
AN AREA THROUGH THIS EVENING SIMILAR TO WHERE IT IS...NAMELY
MOSTLY ALONG AND EAST OF THE BLUE RIDGE FROM TNB-HLX-LYH. WITH THE
UPPER LOW MOVING ALMOST DUE EAST THROUGH THE PERIOD...SEE LITTLE
NORTHWARD PROGRESS OF THE RAIN FROM THESE POINTS...BUT BY THE SAME
TOKEN...LITTLE SOUTHWARD PROGRESS UNTIL THE UPPER LOW MOVES CLOSER
TO THE COAST...ALLOWING DRIER NE FLOW TO ADVECT SOUTHWARD INTO THE
REGION. FOR AREAS FURTHER NORTH AND WEST...CONSIDERABLE HIGH
CLOUDS WILL PERSIST AND EVEN SOME MID CLOUDS ARE EXPECTED TO REACH
THE ALLEGHANY FRONT...BUT LITTLE TO NO PRECIPITATION WEST OF THE
BLUE RIDGE. GFS/ECMWF BOTH CLEARLY DEPICT A SMALL DEFORMATION ZONE
TO DEVELOP ACROSS NORTHWEST NC THIS EVENING...PROLONGING THE
PRECIPITATION IN THAT AREA. HAVE INCREASED POPS TO LIKELY AND
CATEGORICAL AND EXTENDED LONGER INTO OUR SOUTHERN TIER OF COUNTIES
THAN EARLIER ADVERTISED.
SYNOPTIC PATTERN AND -RA...SOME WHAT OF AN INSITU WEDGE REINFORCED
WITH NE FLOW AROUND SE U.S. DEVELOPING SFC LOW PRESSURE...WILL
KEEP THE PIEDMONT THE COOLEST TODAY. HAVE LEANED TOWARD THE ECMWF
MOS...WHICH WAS THE COOLEST AMONG THE MAV/MET/ECS. HOWEVER...EVEN
UNDERCUT IT BY ABOUT ONE CATEGORY IN THE RAINY PIEDMONT AREAS. THE
MOUNTAINS OF NORTHWEST NC WILL STRUGGLE TO REACH 50. THE WARMEST
AREAS TODAY SHOULD BE WEST OF THE ALLEGHANY FRONT...LWB-BLF-
MKJ...WHERE LOW 60S ARE POSSIBLE IF THE CLOUDS THIN OUT ENOUGH
DURING THE MID AND LATE AFTERNOON.
WINDS WILL REMAIN NE EAST OF THE ALLEGHANY FRONT AND GENERALLY
E-SE TO THE WEST. SPEEDS WILL INCREASE DURING THE AFTERNOON AND
EVENING AS A TIGHT PRESSURE GRADIENT DEVELOPS BETWEEN THE LOW
PRESSURE ACROSS SC AND HIGH PRESSURE RIDGING SOUTHWARD FROM NEW
ENGLAND.
&&
.SHORT TERM /SUNDAY THROUGH TUESDAY NIGHT/...
AS OF 400 AM EDT SATURDAY...
FOR EASTER SUNDAY...MAY SEE A FEW RESIDUAL SPRINKLES ACROSS THE
SOUTHSIDE AND THE NORTH CAROLINA PIEDMONT TO START THE DAY...HOWEVER
THESE WILL QUICKLY EXIT THE AREA AS LOW PRESSURE EXITS OFF THE
SOUTHEAST COAST. OTHERWISE...EXPECT CLEARING SKIES AS HIGH PRESSURE
REMAINS WEDGED AGAINST THE EASTERN FACE OF THE APPALACHIANS...
RESULTING IN A LIGHT AND GENERALLY EASTERLY WIND FLOW. WITH THE COOL
HIGH PRESSURE WEDGE IN PLACE...WENT A LITTLE BELOW MODEL GUIDANCE
FOR AFTERNOON TEMPERATURES...WITH HIGHS CLIMBING INTO THE MID AND
UPPER 60S MOST LOCATIONS OUTSIDE OF THE HIGHER RIDGES. LIGHT WINDS
AND MOSTLY CLEAR SKIES WILL ALLOW FOR STRONG RADIATIONAL COOLING
SUNDAY NIGHT...WITH LOWS BOTTOMING OUT IN THE UPPER 30S AND LOW
40S...WITH A FEW MOUNTAIN VALLEYS DROPPING BELOW FREEZING.
UPPER LEVEL RIDGING BECOMES MORE FIRMLY ESTABLISHED FOR MONDAY AS
THE SURFACE HIGH PRESSURE WEDGE SHOWS SIGNS OF BREAKING DOWN.
EXPECT WARMER TEMPERATURES DESPITE INCREASING MID AND HIGH
CLOUDS...WITH HIGHS REACHING INTO THE UPPER 60S AND LOW 70S. WINDS
WILL BECOME INCREASINGLY SOUTHWESTERLY THROUGH THE DAY AHEAD OF AN
APPROACHING COLD FRONT...AND THE WARMER AIR POOLING IN FROM THE
GULF COAST REGION WILL MAKE FOR MILD MONDAY NIGHT LOWS...GENERALLY
IN THE UPPER 40S AND LOW 50S.
SHOWER ACTIVITY WILL ENTER FROM THE WEST AFTER SUNRISE TUESDAY AS
THE COLD FRONT ADVANCES EAST ACROSS KENTUCKY/TENNESSEE. GFS/ECMWF/
CANADIAN FORECAST MODELS ALL INDICATE DECENT INSTABILITY DEVELOPING
DURING THE AFTERNOON ALONG AND EAST OF THE BLUE RIDGE AS A LEE SIDE
TROUGH SETS UP...WHILE STRONG HEATING WILL ALLOW TEMPERATURES TO
CLIMB INTO THE MID AND UPPER 70S. AS SUCH...CONDITIONS APPEAR
FAVORABLE FOR SCATTERED THUNDERSTORMS TO DEVELOP...A FEW OF WHICH
WILL LIKELY BECOME STRONG TO SEVERE. AT THIS POINT...BOTH HAIL AND
GUSTY WINDS WOULD BE CONCERNS. THE COLD FRONT WILL PASS ACROSS THE
AREA DURING THE EVENING...EXITING TO THE EAST AFTER MIDNIGHT
WEDNESDAY. A FEW UPSLOPE RAIN SHOWERS MAY LINGER ACROSS THE WESTERN
RIDGES THROUGH THE NIGHT...OTHERWISE CLEARING CONDITIONS ARE
EXPECTED.
&&
.LONG TERM /WEDNESDAY THROUGH FRIDAY/...
AS OF 400 AM EDT FRIDAY...
BELIEVE THERE WILL STILL BE A CHANCE FOR SOME UPSLOPE RAIN SHOWERS
IN CAA WEST OF THE BLUE RIDGE EARLY WEDNESDAY...IN ADDITION TO
BREEZY CONDITIONS AS HIGH PRESSURE BUILDS IN FROM THE NORTHWEST.
EXPECT QUIET WEATHER FOR THURSDAY AS HIGH PRESSURE PASSES OVERHEAD.
SHOWERS AND POSSIBLE THUNDERSTORMS WILL MOVE IN ON FRIDAY AS ANOTHER
COLD FRONT APPROACHES.
&&
.AVIATION /16Z SATURDAY THROUGH WEDNESDAY/...
AS OF 740 AM EDT SATURDAY...
UPPER LOW PRESSURE AREA SOUTHEAST U.S. WILL CONTINUE TO CLOSE OFF
AND DRIFT VERY SLOWLY EAST ALONG THE GULF COAST TO THE SOUTHEAST
ATLANTIC COAST THROUGH THE PERIOD. MARITIME EASTERLY FLOW ON THE
NORTH SIDE WILL CONTINUE TO ADVECT LIGHT RAIN INTO THE SOUTHERN
PORTION OF THE CWA...INCLUDING DAN. A FEW SPRINKLES MAY REACH
ROA/LYH...BUT NOT ENOUGH TO REDUCE VSBY. THE -RA CONTINUES TO FALL
OUT OF VFR CIGS...MOSTLY AOA 080 AT THIS TIME. VERY DRY MID-
LEVEL AIR WILL CONTINUE TO GRADUALLY MOISTEN...BUT CIGS APPEAR
DESTINED TO REMAIN MOSTLY VFR THROUGH THE TAF VALID PERIOD...BUT
WILL LIKELY LOWER TO LOW END VFR LYH-DAN FOR A PERIOD LATE
MORNING/EARLY AFTERNOON...BEFORE THE DEEPER MOISTURE ASSOCIATED
WITH THE UPPER LOW SPREADS FURTHER EAST LATE AFTERNOON/EVENING.
UNLIKE YESTERDAY MORNING...SFC FLOW NOW NE AS OPPOSED TO
SE...WHICH IS HELPING TO TRANSPORT DRIER AIR INTO THE REGION FROM
THE NORTHEAST MAKING IT HARD TO REALIZE ANYTHING WORSE THAN VFR AT
THIS POINT. OCCASIONAL MVFR VSBYS ARE ALSO POSSIBLE DAN...BUT
ELSEWHERE DO NOT EXPECT ENOUGH -RA TO WARRANT MENTION OF ANY VSBYS
LESS THAN VFR.
WINDS WILL BE ON THE INCREASE AS THE DAY PROGRESSES WITH A
TIGHTENING OF THE PRESSURE GRADIENT BETWEEN NORTHEASTERN U.S. HIGH
PRESSURE AND SOUTHEAST U.S. LOW. EXPECT ENE 10-12KTS WITH GUSTS TO
20KTS ACROSS THE PIEDMONT BY AFTERNOON AND EVENING...DIMINISHING
AFT 00Z...BUT LOW END GUSTS POSSIBLE MUCH OF THE NIGHT ACROSS THE
PIEDMONT.
MEDIUM CONFIDENCE IN CIGS AND VSBYS THROUGH THE TAF VALID PERIOD.
MEDIUM TO HIGH CONFIDENCE IN WIND DIR/SPD THROUGH THE TAF VALID
PERIOD.
EXTENDED AVIATION DISCUSSION... THE UPPER LOW SLOWLY EXITS TO THE
EAST SUNDAY AND HIGH PRESSURE RETURNS BRINGING A RETURN TO VFR
CONDITIONS INTO EARLY NEXT WEEK. THE NEXT COLD FRONT APPROACHES
MONDAY NIGHT WITH MORE SHOWERS AND POSSIBLE THUNDERSTORMS INCLUDING
PERIODS OF MVFR. FRONT EXITS TUESDAY NIGHT RESULTING IN A RETURN TO
VFR WEDNESDAY EXCEPT FOR MVFR CIGS OVER THE FAR WESTERN SITES IN SE
WEST VA.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...RAB
NEAR TERM...JH/RAB
SHORT TERM...NF
LONG TERM...MBS/NF
AVIATION...RAB/RCS
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1002 AM EDT SAT APR 19 2014
.SYNOPSIS...
A DEEP AREA OF LOW PRESSURE ALOFT ACROSS THE SOUTHEAST STATES WILL
MOVE VERY SLOWLY EASTWARD THROUGH THE WEEKEND...MOVING OFF THE
COAST BY MONDAY...KEEPING CLOUDS AND LIGHT RAIN ACROSS SOUTHERN
SECTIONS TODAY INTO EARLY SUNDAY. HIGH PRESSURE WILL BUILD ACROSS
THE REGION FOR LATER SUNDAY INTO MONDAY. BY TUESDAY...A COLD FRONT
AND ASSOCIATED UPPER TROUGH WILL MOVE INTO THE REGION FROM THE
NORTHWEST BRINGING A CHANCE FOR SHOWERS AND THUNDERSTORMS...FOLLOWED
BY BREEZY AND COOLER CONDITIONS FOR THE MID PART OF NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 930 AM EDT SATURDAY...
ELONGATED BAND OF RAIN ASSOCIATED WITH THE MID LEVEL DEFORMATION
ZONE OF THE BROAD UPPER LOW ACROSS NORTH FLORIDA REMAINS ACROSS
THE FAR SOUTHERN TIER THIS MORNING. HOWEVER LATEST MORNING
SOUNDINGS CONTINUE TO SHOW A STRONG NE FLUX OF DRIER AIR IN THE
LOWER LEVELS AS EVIDENCED VIA THE RNK RAOB. THIS HAS CAUSED SOME
DRYING TO TAKE PLACE ALONG THE BLUE RIDGE SOUTH TO NEAR THE
VIRGINIA BORDER WHICH IS CLOSER TO THE LATEST HRRR SOLN THAT
ATTEMPTS TO SHIFT ALL THE PRECIP SOUTH THIS AFTERNOON. GFS
CONTINUES TO MAINTAIN THE AXIS OF LIGHT RAIN WITH MORE EASTERLY
INFLOW OFF THE ATLANTIC AS THE UPPER SYSTEM ONLY DRIFTS TO OFF THE
SE COAST BY THIS EVENING. THIS SCENARIO APPEARS MORE IN LINE WITH
A SHARP GRADIENT FROM SOME SUN NORTH...TO CLOUDS CENTRAL
SECTIONS...WITH CONTINUED PERIODS OF -RA VA/NC BORDER AND POINTS
SOUTH AS THE BAND TENDS TO STRETCH OUT WHILE SLOWLY DIMINISHING
THROUGH THE AFTERNOON. THIS SUPPORTS KEEPING CAT/LIKELY POPS A
WHILE LONGER ACROSS MUCH OF NW NC INTO SOUTHSIDE VIRGINIA WITH A
QUICK DROPOFF TO DRY CONDITIONS FROM JUST SOUTH OF HIWAY 460 AND
POINTS NORTH.
HIGH TEMPS REMAIN TRICKY WITH POTENTIAL FOR HIGHS TO STRUGGLE TO
TOP 50 UNDER THE RAIN WHILE REACHING THE LOW/MID 60S FAR
NORTH/WEST WITH 56-63 BCB-ROA-LYH CORRIDOR PENDING DEGREE OF ANY
BREAKS. THUS INCREASED THE GRADIENT THIS AFTERNOON SINCE ALREADY
ABOVE HIGHS IN SPOTS NORTH OF THE MAIN RAIN/CLOUD SHIELD ATTM.
PREVIOUS DISCUSSION...
MAIN CONCERN THROUGH THE NEAR TERM CONTINUES TO BE SLOW
MOVING...INCREASINGLY VERTICALLY STACKED UPPER LOW ACROSS THE
SOUTHEAST STATES. FINALLY...AFTER SEVERAL DAYS OF DIFFERING
SOLUTIONS AMONG THE MODELS...THE GFS/ECMWF/NAM/CANADIAN HAVE ALL
CONVERGED ON A SIMILAR SOLUTION. EXPECT -RA TO GENERALLY REMAIN IN
AN AREA THROUGH THIS EVENING SIMILAR TO WHERE IT IS...NAMELY
MOSTLY ALONG AND EAST OF THE BLUE RIDGE FROM TNB-HLX-LYH. WITH THE
UPPER LOW MOVING ALMOST DUE EAST THROUGH THE PERIOD...SEE LITTLE
NORTHWARD PROGRESS OF THE RAIN FROM THESE POINTS...BUT BY THE SAME
TOKEN...LITTLE SOUTHWARD PROGRESS UNTIL THE UPPER LOW MOVES CLOSER
TO THE COAST...ALLOWING DRIER NE FLOW TO ADVECT SOUTHWARD INTO THE
REGION. FOR AREAS FURTHER NORTH AND WEST...CONSIDERABLE HIGH
CLOUDS WILL PERSIST AND EVEN SOME MID CLOUDS ARE EXPECTED TO REACH
THE ALLEGHANY FRONT...BUT LITTLE TO NO PRECIPITATION WEST OF THE
BLUE RIDGE. GFS/ECMWF BOTH CLEARLY DEPICT A SMALL DEFORMATION ZONE
TO DEVELOP ACROSS NORTHWEST NC THIS EVENING...PROLONGING THE
PRECIPITATION IN THAT AREA. HAVE INCREASED POPS TO LIKELY AND
CATEGORICAL AND EXTENDED LONGER INTO OUR SOUTHERN TIER OF COUNTIES
THAN EARLIER ADVERTISED.
SYNOPTIC PATTERN AND -RA...SOME WHAT OF AN INSITU WEDGE REINFORCED
WITH NE FLOW AROUND SE U.S. DEVELOPING SFC LOW PRESSURE...WILL
KEEP THE PIEDMONT THE COOLEST TODAY. HAVE LEANED TOWARD THE ECMWF
MOS...WHICH WAS THE COOLEST AMONG THE MAV/MET/ECS. HOWEVER...EVEN
UNDERCUT IT BY ABOUT ONE CATEGORY IN THE RAINY PIEDMONT AREAS. THE
MOUNTAINS OF NORTHWEST NC WILL STRUGGLE TO REACH 50. THE WARMEST
AREAS TODAY SHOULD BE WEST OF THE ALLEGHANY FRONT...LWB-BLF-
MKJ...WHERE LOW 60S ARE POSSIBLE IF THE CLOUDS THIN OUT ENOUGH
DURING THE MID AND LATE AFTERNOON.
WINDS WILL REMAIN NE EAST OF THE ALLEGHANY FRONT AND GENERALLY
E-SE TO THE WEST. SPEEDS WILL INCREASE DURING THE AFTERNOON AND
EVENING AS A TIGHT PRESSURE GRADIENT DEVELOPS BETWEEN THE LOW
PRESSURE ACROSS SC AND HIGH PRESSURE RIDGING SOUTHWARD FROM NEW
ENGLAND.
&&
.SHORT TERM /SUNDAY THROUGH TUESDAY NIGHT/...
AS OF 400 AM EDT SATURDAY...
FOR EASTER SUNDAY...MAY SEE A FEW RESIDUAL SPRINKLES ACROSS THE
SOUTHSIDE AND THE NORTH CAROLINA PIEDMONT TO START THE DAY...HOWEVER
THESE WILL QUICKLY EXIT THE AREA AS LOW PRESSURE EXITS OFF THE
SOUTHEAST COAST. OTHERWISE...EXPECT CLEARING SKIES AS HIGH PRESSURE
REMAINS WEDGED AGAINST THE EASTERN FACE OF THE APPALACHIANS...
RESULTING IN A LIGHT AND GENERALLY EASTERLY WIND FLOW. WITH THE COOL
HIGH PRESSURE WEDGE IN PLACE...WENT A LITTLE BELOW MODEL GUIDANCE
FOR AFTERNOON TEMPERATURES...WITH HIGHS CLIMBING INTO THE MID AND
UPPER 60S MOST LOCATIONS OUTSIDE OF THE HIGHER RIDGES. LIGHT WINDS
AND MOSTLY CLEAR SKIES WILL ALLOW FOR STRONG RADIATIONAL COOLING
SUNDAY NIGHT...WITH LOWS BOTTOMING OUT IN THE UPPER 30S AND LOW
40S...WITH A FEW MOUNTAIN VALLEYS DROPPING BELOW FREEZING.
UPPER LEVEL RIDGING BECOMES MORE FIRMLY ESTABLISHED FOR MONDAY AS
THE SURFACE HIGH PRESSURE WEDGE SHOWS SIGNS OF BREAKING DOWN.
EXPECT WARMER TEMPERATURES DESPITE INCREASING MID AND HIGH
CLOUDS...WITH HIGHS REACHING INTO THE UPPER 60S AND LOW 70S. WINDS
WILL BECOME INCREASINGLY SOUTHWESTERLY THROUGH THE DAY AHEAD OF AN
APPROACHING COLD FRONT...AND THE WARMER AIR POOLING IN FROM THE
GULF COAST REGION WILL MAKE FOR MILD MONDAY NIGHT LOWS...GENERALLY
IN THE UPPER 40S AND LOW 50S.
SHOWER ACTIVITY WILL ENTER FROM THE WEST AFTER SUNRISE TUESDAY AS
THE COLD FRONT ADVANCES EAST ACROSS KENTUCKY/TENNESSEE. GFS/ECMWF/
CANADIAN FORECAST MODELS ALL INDICATE DECENT INSTABILITY DEVELOPING
DURING THE AFTERNOON ALONG AND EAST OF THE BLUE RIDGE AS A LEE SIDE
TROUGH SETS UP...WHILE STRONG HEATING WILL ALLOW TEMPERATURES TO
CLIMB INTO THE MID AND UPPER 70S. AS SUCH...CONDITIONS APPEAR
FAVORABLE FOR SCATTERED THUNDERSTORMS TO DEVELOP...A FEW OF WHICH
WILL LIKELY BECOME STRONG TO SEVERE. AT THIS POINT...BOTH HAIL AND
GUSTY WINDS WOULD BE CONCERNS. THE COLD FRONT WILL PASS ACROSS THE
AREA DURING THE EVENING...EXITING TO THE EAST AFTER MIDNIGHT
WEDNESDAY. A FEW UPSLOPE RAIN SHOWERS MAY LINGER ACROSS THE WESTERN
RIDGES THROUGH THE NIGHT...OTHERWISE CLEARING CONDITIONS ARE
EXPECTED.
&&
.LONG TERM /WEDNESDAY THROUGH FRIDAY/...
AS OF 400 AM EDT FRIDAY...
BELIEVE THERE WILL STILL BE A CHANCE FOR SOME UPSLOPE RAIN SHOWERS
IN CAA WEST OF THE BLUE RIDGE EARLY WEDNESDAY...IN ADDITION TO
BREEZY CONDITIONS AS HIGH PRESSURE BUILDS IN FROM THE NORTHWEST.
EXPECT QUIET WEATHER FOR THURSDAY AS HIGH PRESSURE PASSES OVERHEAD.
SHOWERS AND POSSIBLE THUNDERSTORMS WILL MOVE IN ON FRIDAY AS ANOTHER
COLD FRONT APPROACHES.
&&
.AVIATION /14Z SATURDAY THROUGH WEDNESDAY/...
AS OF 740 AM EDT SATURDAY...
UPPER LOW PRESSURE AREA SOUTHEAST U.S. WILL CONTINUE TO CLOSE OFF
AND DRIFT VERY SLOWLY EAST ALONG THE GULF COAST TO THE SOUTHEAST
ATLANTIC COAST THROUGH THE PERIOD. MARITIME EASTERLY FLOW ON THE
NORTH SIDE WILL CONTINUE TO ADVECT LIGHT RAIN INTO THE SOUTHERN
PORTION OF THE CWA...INCLUDING DAN. A FEW SPRINKLES MAY REACH
ROA/LYH...BUT NOT ENOUGH TO REDUCE VSBY. THE -RA CONTINUES TO FALL
OUT OF VFR CIGS...MOSTLY AOA 080 AT THIS TIME. VERY DRY MID-
LEVEL AIR WILL CONTINUE TO GRADUALLY MOISTEN...BUT CIGS APPEAR
DESTINED TO REMAIN MOSTLY VFR THROUGH THE TAF VALID PERIOD...BUT
WILL LIKELY LOWER TO LOW END VFR LYH-DAN FOR A PERIOD LATE
MORNING/EARLY AFTERNOON...BEFORE THE DEEPER MOISTURE ASSOCIATED
WITH THE UPPER LOW SPREADS FURTHER EAST LATE AFTERNOON/EVENING.
UNLIKE YESTERDAY MORNING...SFC FLOW NOW NE AS OPPOSED TO
SE...WHICH IS HELPING TO TRANSPORT DRIER AIR INTO THE REGION FROM
THE NORTHEAST MAKING IT HARD TO REALIZE ANYTHING WORSE THAN VFR AT
THIS POINT. OCCASIONAL MVFR VSBYS ARE ALSO POSSIBLE DAN...BUT
ELSEWHERE DO NOT EXPECT ENOUGH -RA TO WARRANT MENTION OF ANY VSBYS
LESS THAN VFR.
WINDS WILL BE ON THE INCREASE AS THE DAY PROGRESSES WITH A
TIGHTENING OF THE PRESSURE GRADIENT BETWEEN NORTHEASTERN U.S. HIGH
PRESSURE AND SOUTHEAST U.S. LOW. EXPECT ENE 10-12KTS WITH GUSTS TO
20KTS ACROSS THE PIEDMONT BY AFTERNOON AND EVENING...DIMINISHING
AFT 00Z...BUT LOW END GUSTS POSSIBLE MUCH OF THE NIGHT ACROSS THE
PIEDMONT.
MEDIUM CONFIDENCE IN CIGS AND VSBYS THROUGH THE TAF VALID PERIOD.
MEDIUM TO HIGH CONFIDENCE IN WIND DIR/SPD THROUGH THE TAF VALID
PERIOD.
EXTENDED AVIATION DISCUSSION... THE UPPER LOW SLOWLY EXITS TO THE
EAST SUNDAY AND HIGH PRESSURE RETURNS BRINGING A RETURN TO VFR
CONDITIONS INTO EARLY NEXT WEEK. THE NEXT COLD FRONT APPROACHES
MONDAY NIGHT WITH MORE SHOWERS AND POSSIBLE THUNDERSTORMS INCLUDING
PERIODS OF MVFR. FRONT EXITS TUESDAY NIGHT RESULTING IN A RETURN TO
VFR WEDNESDAY EXCEPT FOR MVFR CIGS OVER THE FAR WESTERN SITES IN SE
WEST VA.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...RAB
NEAR TERM...JH/RAB
SHORT TERM...NF
LONG TERM...MBS/NF
AVIATION...RAB/RCS
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1058 AM MDT SAT APR 19 2014
.UPDATE...
ISSUED AT 1046 AM MDT SAT APR 19 2014
FORECAST PRETTY WELL ON TRACK FOR TODAY. ONLY CONCERN IS THICK
CIRRUS OVER MOST OF THE SOUTHEAST FORECAST INHIBITING
THUNDERSTORM CHANCES TODAY. COOL NORTHEAST UPSLOPE WILL NOT HELP
WITH SURFACE BASED INSTABILITY EAST OF THE LARAMIE RANGE AND WINDS
WILL BE SLOWER TO COME AROUND TO THE SOUTH THAN MODELS EARLIER
PROJECTED. NAM AND GFS HAS BACKED OFF ON THE SLIGHTLY NEGATIVE
LIFTED INDEX AND LOOKING AT MODEL SOUNDINGS...STEEP SURFACE BASED
LAPSE RATES WILL BE TOUGH TO COME BY EAST OF THE LARAMIE RANGE.
REMOVED THUNDERSTORM MENTION EAST OF THE LARAMIE RANGE FOR
TODAY...BUT KEPT IT GOING TO THE WEST WHERE MORNING SUNSHINE WILL
PRODUCE THOSE STEEPER LAPSE RATES. CAN NOT COMPLETELY RULE OUT
SOME ELEVATED CONVECTION WITH LIGHTNING EVEN EAST OF THE LARAMIE
RANGE AS THE NORTHERN FRINGES OF AN UPPER LEVEL DISTURBANCE WILL
IMPACT THE SOUTHERN CWA...BUT WITH ONLY WEAK FORCING...LIGHTNING
CHANCES ARE REMOTE AT BEST. GUSTY WINDS AND SMALL GRAUPLE
CERTAINLY A POSSIBILITY WEST OF THE LARAMIE RANGE WITH ANY
STRONGER CONVECTION...BUT SEVERE THUNDERSTORMS NOT LIKELY.
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 256 AM MDT SAT APR 19 2014
AN UPPER LEVEL DISTURBANCE WILL MOVE OVER THE FORECAST AREA THIS
AFTERNOON...WITH SURFACE WINDS VEERING TO THE SOUTHEAST ACROSS THE
PLAINS AND INCREASING IN STRENGTH. DEW POINTS WILL INCREASE INTO THE
UPPER 30S TO LOW 40S ACROSS THE PLAINS IN THIS MOISTURE ADVECTION
PATTERN WITH WEAK INSTABILITY PROGGED FOR THE AFTERNOON. HIGH CLOUD
COVER WILL KEEP TEMPS ON THE COOL SIDE AND THUS INSTABILITY WILL
BE LOW...BUT THE COMBO OF UPPER SUPPORT AND WEAK INSTABILITY WILL
SUPPORT A GOOD CHANCE FOR RAIN SHOWERS WITH ISOLATED THUNDERSTORMS
THIS AFTERNOON ESPECIALLY FOR THE MOUNTAINS AND NEARBY PLAINS.
LOOKS AS THOUGH AREAS FROM THE LARAMIE RANGE TO THE I-25 CORRIDOR
COULD SEE THE BEST CHANCE FOR STORMS OUTSIDE THE MOUNTAINS WHERE
NAM PAINTS INSTABILITY AS HIGH AS 200 J/KG WITHIN THE
BEST...ALBEIT RELATIVELY WEAK...MOISTURE CONVERGENCE ZONE. SHOULD
SEE WETTING RAINS WITH THIS ACTIVITY AS PRECIPITABLE WATER VALUES
WILL INCREASE TO BETWEEN ONE HALF AND THREE QUARTERS OF AN INCH
THROUGH THE AFTERNOON. CONVECTION WILL DIMINISH THROUGH THE
EVENING AS THE UPPER WAVE WEAKENS AND MOVES EAST.
FOR SUNDAY...A COLD FRONT ASSOCIATED WITH A SHORTWAVE MOVING ACROSS
US/CANADIAN BORDER WILL DROP SOUTH ACROSS THE EASTERN PLAINS IN THE
AFTERNOON. TEMPS WILL WARM INTO THE UPPER 60S TO UPPER 70S IN THE
LOWER ELEVATIONS AHEAD OF THE FRONT...WITH LI`S DROPPING TO AROUND
ZERO. TIMING OF THE FRONT COULD FAVOR DEVELOPMENT OF AFTERNOON
SHOWERS AND A FEW WEAK THUNDERSTORMS...ESPECIALLY ALONG THE LARAMIE
RANGE AND CHEYENNE RIDGE WHERE LLVL FORCING AND INSTABILITY ARE
MAXIMIZED. A WEAK DISTURBANCE MOVING OVERHEAD FROM THE WEST WILL
TRIGGER A FEW TSTORMS OVER THE MOUNTAINS IN THE AFTERNOON AS WELL.
SFC HIGH PRESSURE WILL BUILD IN BEHIND THE FRONT FOR MONDAY WITH MAX
TEMPS EXPECTED TO BE ABOUT 5F COOLER. SFC WINDS WILL VEER BACK TO
THE SOUTH-SOUTHEAST IN THE AFTERNOON AND SO MAY SEE A FEW RAIN
SHOWERS DEVELOP WITHIN THE CONVERGENCE ZONE VCTY LARAMIE RANGE. COOLER
SFC TEMPS AND WAA ALOFT DUE TO A BUILDING UPPER RIDGE FROM THE WEST
WILL MINIMIZE INSTABILITY AND THUS TSTORM CHANCES.
.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 256 AM MDT SAT APR 19 2014
PRETTY STRONG LOW PRESSURE SYSTEM IN THE EXTENDED EXPECTED TO
BRING VERY STRONG WINDS AND SOME PRECIP CHANCES TO THE CWFA. THESE
ARE THE CHALLENGES IN THE LONG TERM.
FOR MONDAY NIGHT INTO TUESDAY...UPPER LEVEL RIDGING BUILDS INTO
THE AREA WITH 700MB TEMPERATURES CLIMBING FROM +4C MONDAY
AFTERNOON UP TO +8C TUESDAY AFTERNOON. LOOKS LIKE A PRETTY WARM
DAY TUESDAY WITH 80S RETURNING TO THE PANHANDLE AND UPPER 60S/LOW
70S FOR AREAS WEST OF THE LARAMIE RANGE.
A STRONG UPPER LEVEL LOW PRESSURE SYSTEM MOVES INTO SOUTHERN
NEVADA TO NORTHERN UTAH TUESDAY AFTERNOON...THEN INTO WESTERN
WYOMING TUESDAY NIGHT. AHEAD OF THIS LOW...700MB WINDS BECOME
QUITE STRONG WITH THE GFS SHOW 50KTS AT 700MBS WEDNESDAY MORNING.
700MB CRAIG TO CASPER HEIGHT GRADIENT AT 60MTRS TUESDAY NIGHT AND
INCREASES TO 70MTRS DURING THE MORNING WEDNESDAY. WILL NEED TO
MONITOR THIS FOR POSSIBLE WIND HEADLINES DURING THIS
TIME FRAME...AT LEAST FOR OUR WIND PRONE AREAS.
COLD FRONT ASSOCIATED WITH THIS LOW LOOKS TO MOVE INTO THE AREA
WEDNESDAY AFTERNOON WITH 700MB TEMPERATURES FALLING TO -6C ACROSS
CARBON COUNTY WEDNESDAY NIGHT. FOR NOW...BEST CHANCES FOR PRECIP
LOOK TO BE THE MOUNTAINS AND AREAS WEST OF THE LARAMIE RANGE.
AREAS EAST WILL BE IMPACTED BY DOWNSLOPING WINDS...SO KEPT THESE
AREAS DRY.
CONCERNS FOR WIND HEADLINES SHIFTS EAST INTO THE PANHANDLE
WEDNESDAY NIGHT AS GFS 850MB WINDS INCREASE TO 40KTS. SHOULD BE AT
LEAST WIND ADVISORY CRITERIA OUT THERE...CONTINUING INTO THURSDAY
AFTERNOON.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 506 AM MDT SAT APR 19 2014
CONFIDENCE A LITTLE HIGHER FOR TSTMS TO DEVELOP ACROSS SOUTHERN
WYOMING AND THE SOUTHERN PANHANDLE THIS AFTERNOON AND EVENING.
LATEST HRRR FORECAST SHOWING CONVECTION DEVELOPING AS EARLY AS 18Z
AND PERSISTING THROUGH 00Z FOR KCYS AND KRWL. FOLLOWED THIS
GUIDANCE IN TAFS. CONVECTION COULD MAKE IT TO KBFF AFTER 00Z...BUT
WILL HOLD OFF FOR NOW ON TSTMS.
&&
.FIRE WEATHER...
ISSUED AT 256 AM MDT SAT APR 19 2014
TEMPERATURES WILL BE COOLER TODAY WITH HIGHER HUMIDITIES AND LESS
WIND. CHANCES FOR WETTING RAINS AND ISOLATED THUNDERSTORMS WILL
INCREASE THIS AFTERNOON AND WILL CONTINUE THROUGH THE EVENING AS A
WEATHER DISTURBANCE TRACKS ACROSS THE REGION. ANOTHER COLD FRONT
WILL DROP SOUTH ACROSS THE AREA ON SUNDAY AND WILL BRING A SLIGHT
CHANCE FOR AFTERNOON SHOWERS AND THUNDERSTORMS...ESPECIALLY FOR THE
MOUNTAINS AND AREAS NEAR THE COLORADO BORDER. AFTER A COOLER DAY
MONDAY...EXPECT WARMER AND DRIER CONDITIONS FOR TUESDAY WITH WINDY
CONDITIONS POSSIBLE FOR WEDNESDAY.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
UPDATE...SML
SHORT TERM...RJM
LONG TERM...CLAYCOMB
AVIATION...CLAYCOMB
FIRE WEATHER...RJM
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
509 AM MDT SAT APR 19 2014
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 256 AM MDT SAT APR 19 2014
AN UPPER LEVEL DISTURBANCE WILL MOVE OVER THE FORECAST AREA THIS
AFTERNOON...WITH SURFACE WINDS VEERING TO THE SOUTHEAST ACROSS THE
PLAINS AND INCREASING IN STRENGTH. DEW POINTS WILL INCREASE INTO THE
UPPER 30S TO LOW 40S ACROSS THE PLAINS IN THIS MOISTURE ADVECTION
PATTERN WITH WEAK INSTABILITY PROGGED FOR THE AFTERNOON. HIGH CLOUD
COVER WILL KEEP TEMPS ON THE COOL SIDE AND THUS INSTABILITY WILL
BE LOW...BUT THE COMBO OF UPPER SUPPORT AND WEAK INSTABILITY WILL
SUPPORT A GOOD CHANCE FOR RAIN SHOWERS WITH ISOLATED THUNDERSTORMS
THIS AFTERNOON ESPECIALLY FOR THE MOUNTAINS AND NEARBY PLAINS.
LOOKS AS THOUGH AREAS FROM THE LARAMIE RANGE TO THE I-25 CORRIDOR
COULD SEE THE BEST CHANCE FOR STORMS OUTSIDE THE MOUNTAINS WHERE
NAM PAINTS INSTABILITY AS HIGH AS 200 J/KG WITHIN THE
BEST...ALBEIT RELATIVELY WEAK...MOISTURE CONVERGENCE ZONE. SHOULD
SEE WETTING RAINS WITH THIS ACTIVITY AS PRECIPITABLE WATER VALUES
WILL INCREASE TO BETWEEN ONE HALF AND THREE QUARTERS OF AN INCH
THROUGH THE AFTERNOON. CONVECTION WILL DIMINISH THROUGH THE
EVENING AS THE UPPER WAVE WEAKENS AND MOVES EAST.
FOR SUNDAY...A COLD FRONT ASSOCIATED WITH A SHORTWAVE MOVING ACROSS
US/CANADIAN BORDER WILL DROP SOUTH ACROSS THE EASTERN PLAINS IN THE
AFTERNOON. TEMPS WILL WARM INTO THE UPPER 60S TO UPPER 70S IN THE
LOWER ELEVATIONS AHEAD OF THE FRONT...WITH LI`S DROPPING TO AROUND
ZERO. TIMING OF THE FRONT COULD FAVOR DEVELOPMENT OF AFTERNOON
SHOWERS AND A FEW WEAK THUNDERSTORMS...ESPECIALLY ALONG THE LARAMIE
RANGE AND CHEYENNE RIDGE WHERE LLVL FORCING AND INSTABILITY ARE
MAXIMIZED. A WEAK DISTURBANCE MOVING OVERHEAD FROM THE WEST WILL
TRIGGER A FEW TSTORMS OVER THE MOUNTAINS IN THE AFTERNOON AS WELL.
SFC HIGH PRESSURE WILL BUILD IN BEHIND THE FRONT FOR MONDAY WITH MAX
TEMPS EXPECTED TO BE ABOUT 5F COOLER. SFC WINDS WILL VEER BACK TO
THE SOUTH-SOUTHEAST IN THE AFTERNOON AND SO MAY SEE A FEW RAIN
SHOWERS DEVELOP WITHIN THE CONVERGENCE ZONE VCTY LARAMIE RANGE. COOLER
SFC TEMPS AND WAA ALOFT DUE TO A BUILDING UPPER RIDGE FROM THE WEST
WILL MINIMIZE INSTABILITY AND THUS TSTORM CHANCES.
.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 256 AM MDT SAT APR 19 2014
PRETTY STRONG LOW PRESSURE SYSTEM IN THE EXTENDED EXPECTED TO
BRING VERY STRONG WINDS AND SOME PRECIP CHANCES TO THE CWFA. THESE
ARE THE CHALLENGES IN THE LONG TERM.
FOR MONDAY NIGHT INTO TUESDAY...UPPER LEVEL RIDGING BUILDS INTO
THE AREA WITH 700MB TEMPERATURES CLIMBING FROM +4C MONDAY
AFTERNOON UP TO +8C TUESDAY AFTERNOON. LOOKS LIKE A PRETTY WARM
DAY TUESDAY WITH 80S RETURNING TO THE PANHANDLE AND UPPER 60S/LOW
70S FOR AREAS WEST OF THE LARAMIE RANGE.
A STRONG UPPER LEVEL LOW PRESSURE SYSTEM MOVES INTO SOUTHERN
NEVADA TO NORTHERN UTAH TUESDAY AFTERNOON...THEN INTO WESTERN
WYOMING TUESDAY NIGHT. AHEAD OF THIS LOW...700MB WINDS BECOME
QUITE STRONG WITH THE GFS SHOW 50KTS AT 700MBS WEDNESDAY MORNING.
700MB CRAIG TO CASPER HEIGHT GRADIENT AT 60MTRS TUESDAY NIGHT AND
INCREASES TO 70MTRS DURING THE MORNING WEDNESDAY. WILL NEED TO
MONITOR THIS FOR POSSIBLE WIND HEADLINES DURING THIS
TIME FRAME...AT LEAST FOR OUR WIND PRONE AREAS.
COLD FRONT ASSOCIATED WITH THIS LOW LOOKS TO MOVE INTO THE AREA
WEDNESDAY AFTERNOON WITH 700MB TEMPERATURES FALLING TO -6C ACROSS
CARBON COUNTY WEDNESDAY NIGHT. FOR NOW...BEST CHANCES FOR PRECIP
LOOK TO BE THE MOUNTAINS AND AREAS WEST OF THE LARAMIE RANGE.
AREAS EAST WILL BE IMPACTED BY DOWNSLOPING WINDS...SO KEPT THESE
AREAS DRY.
CONCERNS FOR WIND HEADLINES SHIFTS EAST INTO THE PANHANDLE
WEDNESDAY NIGHT AS GFS 850MB WINDS INCREASE TO 40KTS. SHOULD BE AT
LEAST WIND ADVISORY CRITERIA OUT THERE...CONTINUING INTO THURSDAY
AFTERNOON.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 506 AM MDT SAT APR 19 2014
CONFIDENCE A LITTLE HIGHER FOR TSTMS TO DEVELOP ACROSS SOUTHERN
WYOMING AND THE SOUTHERN PANHANDLE THIS AFTERNOON AND EVENING.
LATEST HRRR FORECAST SHOWING CONVECTION DEVELOPING AS EARLY AS 18Z
AND PERSISTING THROUGH 00Z FOR KCYS AND KRWL. FOLLOWED THIS
GUIDANCE IN TAFS. CONVECTION COULD MAKE IT TO KBFF AFTER 00Z...BUT
WILL HOLD OFF FOR NOW ON TSTMS.
&&
.FIRE WEATHER...
ISSUED AT 256 AM MDT SAT APR 19 2014
TEMPERATURES WILL BE COOLER TODAY WITH HIGHER HUMIDITIES AND LESS
WIND. CHANCES FOR WETTING RAINS AND ISOLATED THUNDERSTORMS WILL
INCREASE THIS AFTERNOON AND WILL CONTINUE THROUGH THE EVENING AS A
WEATHER DISTURBANCE TRACKS ACROSS THE REGION. ANOTHER COLD FRONT
WILL DROP SOUTH ACROSS THE AREA ON SUNDAY AND WILL BRING A SLIGHT
CHANCE FOR AFTERNOON SHOWERS AND THUNDERSTORMS...ESPECIALLY FOR THE
MOUNTAINS AND AREAS NEAR THE COLORADO BORDER. AFTER A COOLER DAY
MONDAY...EXPECT WARMER AND DRIER CONDITIONS FOR TUESDAY WITH WINDY
CONDITIONS POSSIBLE FOR WEDNESDAY.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
SHORT TERM...RJM
LONG TERM...CLAYCOMB
AVIATION...CLAYCOMB
FIRE WEATHER...RJM
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1108 PM MDT SUN APR 20 2014
.UPDATE...
ISSUED AT 850 PM MDT SUN APR 20 2014
UPDATED TO TREND POPS WITH THE LATEST RADAR DATA. SINCE SUN
DOWN...MOST OF THE SHOWER ACTIVITY HAS DISSIPATED ACROSS SOUTHERN
COLORADO. THE EXCEPTIONS ARE OVER THE PALMER DIVIDE WHERE NEW
DEVELOPMENT HAS BEEN PUSHING SOUTH...AND OVER THE EASTERN
MOUNTAINS AND ADJACENT PLAINS WEST OF I-25 WHERE WEAK ACTIVITY
CONTINUES. HAVE MAINTAINED THESE AREAS SEEING SHOWER ACTIVITY AND
ISOLATED THUNDERSTORMS THROUGH MIDNIGHT. ELSEWHERE...DRY
CONDITIONS WILL PREVAIL INTO MONDAY MORNING. MOZLEY
UPDATE ISSUED AT 550 PM MDT SUN APR 20 2014
ONLY MINOR UPDATES TO THE GOING FORECAST THIS EVENING. AN UPPER
LOW IS SITTING OVER FAR SOUTHWEST KANSAS WITH BROAD NORTHERLY FLOW
ACROSS EASTERN COLORADO. WEAK SHOWER ACTIVITY CONTINUES ACROSS THE
I-25 CORRIDOR AND EASTERN MOUNTAINS WITH ISOLATED THUNDERSTORMS.
STRONGER THUNDERSTORM ACTIVITY IS CURRENTLY SITUATED NEAR THE
UPPER LEVEL DISTURBANCE ALONG THE KANSAS BORDER. LIGHTNING ALONG
WITH 40 MPH OUTFLOW WINDS AND PEA SIZE HAIL ARE ALL POSSIBLE IN
THE STORMS NEAR THE KANSAS BORDER.
MODELS RAPIDLY DISSIPATE SHOWER ACTIVITY AFTER SUNSET WITH ALL
AREAS DRY BY MIDNIGHT. AREAS OUT EAST NEAR THE KANSAS BORDER AND
AREAS DOWN SOUTH ALONG THE NEW MEXICO BORDER WILL HOLD OUT THE
LONGEST. MOZLEY
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 330 PM MDT SUN APR 20 2014
UPPER LOW OVER SE CO/NW NM AND THE TX/OK PANHANDLES WILL CONTINUE
MOVING EAST THIS EVENING. SHOWERS AND THUNDERSTORMS HAVE DEVELOPED
ACROSS SOUTHEAST CO ON THE NORTHWEST SIDE OF THE UPPER LOW IN AREA
OF WEAK ISENTROPIC UPGLIDE AND INSTABILITY. RESIDUAL MOISTURE
ACROSS THE AREA BEHIND THE SYSTEM HAS BEEN SUFFICIENT TO TRIGGER
SOME SCATTERED SHOWERS ACROSS THE MOUNTAINS WITH SOME AFTERNOON
HEATING...AND APPEARS THAT TAIL END OF PASSING SHORTWAVE TO THE
NORTH MAY BE AIDING THUNDERSTORM INITIATION ACROSS NW CO. THIS
LATTER FEATURE WILL CLIP THROUGH NRN CO THIS AFTERNOON AND EVENING.
MAIN CONCERN FOR THE SHORT TERM WILL BE POTENTIAL FOR RUN-OFF
PRODUCING RAINFALL ON THE BURN SCARS. OF GREATER CONCERN WILL BE
THE EAST PEAK BURN SCAR WHERE RAINFALL OCCURRED EARLIER THIS
MORNING. RADAR ESTIMATES COMPARED WITH GAGES IN THE AREA SUGGEST
THAT PORTIONS OF THE BURN SCAR MAY HAVE RECEIVED .50 TO .70 OF
RAINFALL. THIS OCCURRED SLOWLY THOUGH WITH RATES UNDER .10 TO .20
PER HOUR...SO NO PROBLEMS WERE NOTED. HOWEVER IF THIS AREA WERE TO
GET HIT WITH A STRONGER CELL THIS AFTERNOON OR EVENING...THE
SATURATED GROUND MAY RESULT IN SOME QUICK RUN-OFF PROBLEMS.
HOWEVER...CLOUD COVER IN THIS AREA MAY ALSO HELP KEEP THE
ATMOSPHERE MORE STABLE...SO RISK SEEMS LOW AT THIS POINT.
A LITTLE BETTER HEATING HAS BEEN REALIZED FARTHER NORTH ACROSS THE
PIKES PEAK REGION. HOWEVER...DEW POINTS HAVE BEEN DROPPING INTO THE
LOWER 30S AND LATEST HRRR DROPS THEM INTO THE UPPER 20S BY LATE
AFTERNOON WHICH REALLY CUTS BACK ON THE INSTABILITY AND RESULTANT
THUNDERSTORM STRENGTH. WHILE CAN`T ENTIRELY RULE OUT AN ISOLATED
STRONGER CELL IMPACTING THE WALDO CANYON BURN SCAR...THINK THIS
CHANCE IS FAIRLY LOW...AND IF IT DID WOULD PROBABLY NOT LAST LONG
ENOUGH TO PRODUCE MUCH MORE THAN SOME MINOR RUN-OFF ISSUES AT BEST.
ALSO...WATCHING THE SOUTHEAST PLAINS OF THE STATE IN VCNTY OF UPPER
LOW...WHERE LOW LEVEL LAPSE RATES COULD BECOME STEEP ENOUGH TO
PRODUCE A SHORT LIVED NON-SUPERCELL TORNADO/LANDSPOUT. SO
FAR...UPDRAFT STRENGTHS HAVEN`T BEEN STRONG ENOUGH TO STRETCH ANY
LOW LEVEL VORTICITY...BUT WILL CONTINUE TO WATCH IT CLOSELY AS SPC
MESO-ANALYSIS DOES SHOW A POCKET OF HIGH NON-SUPERCELL TOR INDICES
ACROSS PORTIONS OF THE AREA.
ALL ACTIVITY SHIFTS TO THE EAST AND SOUTHEAST FAIRLY QUICKLY THROUGH
LATE AFTERNOON AND EARLY EVENING...SO THESE THREATS SHOULD QUICKLY
COME TO AN END WITH THE LOSS OF HEATING.
ON MONDAY...UPPER RIDGE TRANSLATES IN...BUT THERE WILL STILL BE
ENOUGH RESIDUAL MOISTURE FOR ISOLATED SHOWERS AND THUNDERSTORMS IN
AND NEAR THE MOUNTAINS. OTHERWISE...TEMPERATURES SHOULD BE A LITTLE
WARMER THAN TODAYS...ESPECIALLY IN AND NEAR THE SOUTHEAST MOUNTAINS
WHERE CLOUDS HAVE HELD TEMPERATURES DOWN TODAY. -KT
.LONG TERM...(MONDAY NIGHT THROUGH NEXT SUNDAY)
ISSUED AT 330 PM MDT SUN APR 20 2014
NOT MANY ADJUSTMENTS NEEDED FROM PREVIOUS LONGER TERM THINKING WITH
MAIN LONGER TERM ISSUES BEING ABOVE CLIMATOLOGICAL TEMPERATURES FROM
MONDAY NIGHT INTO EARLY NEXT WEEKEND...ISOLATED TO SCATTERED
POPS...PRIMARILY OVER HIGHER TERRAIN LOCATIONS AT TIMES FROM MONDAY
NIGHT INTO WEDNESDAY AND THEN AGAIN BY NEXT WEEKEND...INCREASING
FIRE WEATHER CONCERNS...BEGINNING WEDNESDAY AFTERNOON AS WELL AS AN
INCREASING POTENTIAL FOR STRONGER TO POSSIBLY SEVERE THUNDERSTORMS
OVER SECTIONS OF THE SOUTHEASTERN COLORADO PLAINS FROM LATER
FRIDAY INTO NEXT WEEKEND.
LATEST LONGER TERM COMPUTER SIMULATIONS AND FORECAST MODEL SOUNDINGS
SUGGEST THAT VARYING DEGREES OF ZONAL TO SOUTHWESTERLY UPPER FLOW
WILL OCCUR OVER THE FORECAST DISTRICT FROM MONDAY NIGHT INTO FRIDAY
MORNING. ISOLATED TO SCATTERED SHOWERS AS WELL AS ISOLATED
THUNDERSTORMS ARE ANTICIPATED OVER PORTIONS OF THE CWFA FROM MONDAY
EVENING INTO WEDNESDAY...FAVORING LOCATIONS SUCH AS THE CENTRAL
MOUNTAINS.
FOCUS THEN SHIFTS TO INCREASING FIRE WEATHER CONCERNS AT
TIMES(ESPECIALLY OVER EASTERN SECTIONS AS WELL AS THE SAN LUIS
VALLEY)...PRIMARILY DURING WEDNESDAY AFTERNOON AND EVENING AND
THEN POSSIBLY CONTINUING AT TIMES INTO EARLY NEXT WEEKEND. WFO
PUEBLO WILL CONTINUE TO MONITOR CLOSELY.
IN ADDITION...METEOROLOGICAL PARAMETERS ARE BEGINNING TO SIGNAL
AN INCREASING POTENTIAL FOR STRONG TO POSSIBLY SEVERE
THUNDERSTORM ACTIVITY OVER PORTIONS OF THE SOUTHEASTERN COLORADO
PLAINS FROM LATER FRIDAY INTO NEXT WEEKEND AS UPPER SYSTEM IMPACTS
THE FORECAST DISTRICT. AS ALWAYS...WFO PUEBLO WILL ALSO CONTINUE
TO MONITOR THESE TRENDS CLOSELY.
SWITCHING FOCUS TO TEMPERATURES...IT STILL APPEARS THAT BOTH MINIMUM
AND MAXIMUM TEMPERATURES WILL RUN ABOVE LATE APRIL CLIMATOLOGICAL
AVERAGES FROM MONDAY NIGHT INTO NEXT SATURDAY BEFORE TEMPERATURES
DECREASE BY NEXT SUNDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1107 PM MDT SUN APR 20 2014
KALS...VFR CONDITIONS EXPECTED THROUGH THE NEXT 24 HOURS. THERE IS
A LOW CHANCE FOR SHOWERS AND THUNDERSTORMS OVER THE SAN LUIS
VALLEY ON MONDAY AFTERNOON...WHICH MAY IMPACT THE TERMINAL. IF A
SHOWER MOVES OVER THE TERMINAL...IT WOULD PRODUCE BRIEF PERIODS OF
REDUCED CIGS AND VIS.
KCOS AND KPUB...VFR CONDITIONS THROUGH THE NEXT 24 HOURS. WINDS
WILL BE DIURNALLY DRIVEN WITH MID AND HIGH CLOUD DECKS. MOZLEY
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...MOZLEY
AVIATION...MOZLEY
AREA FORECAST DISCUSSION
NWS DES MOINES IA
343 AM CDT MON APR 21 2014
.SHORT TERM /TODAY/...
ISSUED AT 343 AM CDT MON APR 21 2014
STUBBORN COLD FRONT WILL FINALLY SWING THROUGH THE STATE
TODAY AND BRING SCATTERED SHOWERS AND A FEW THUNDERSTORMS TO THE
FORECAST AREA DURING MUCH OF THE MORNING. FRONT LOOKS TO CREEP INTO
NORTHWEST PORTIONS OF THE FORECAST AREA BY AROUND 14-15Z AND
CONTINUE TO PUSH SOUTHEAST AND CLEAR MUCH OF THE FORECAST AREA BY
AROUND 00Z TUESDAY OR SLIGHTLY SOONER. LEANED TOWARD THE SLOWER
SREF/GFS/ECMWF WRT TO WINDS AND TEMPERATURES TODAY. 21.05Z HRRR IS A
LITTLE TOO FAST WITH THE PRECIP MOVING EAST AND THE 21.03Z HOPWRF IS
LIGHTER ON THE COVERAGE. REGARDLESS...UTILIZED A BLEND OF THE TWO
FOR POPS/WX TRENDS THROUGH MIDDAY TODAY...THEN THE 21.03Z
SREF/21.00Z HIRES-ARW/NMM FOR TRENDS THIS AFTERNOON.
SURFACE LOW LOCATED OVER NORTHWEST IOWA/SOUTHWEST MINNESOTA WITH
COLD FRONT EXTENDING SOUTHWEST INTO NEBRASKA. WEAK AND BROAD LARGE
SCALE FORCING AHEAD THIS COLD FRONT AS WELL AS ISENTROPIC LIFT WILL
CONTINUE TO FEED MOISTURE INTO THE FORECAST AREA THIS MORNING.
INSTABILITY NOT IMPRESSIVE TODAY BUT ENOUGH AVAILABLE TO KEEP
MENTION OF THUNDER. HAVE BULK OF THE HIGHER POPS OVER WESTERN AND
NORTHERN IOWA THROUGH 12-14Z BEFORE SHIFTING FURTHER SOUTHEAST LATE
THIS MORNING. BELIEVE MUCH OF THE PRECIP WILL QUICKLY DISSIPATE PAST
18-20Z OR BE CONFINED TO THE SOUTHEAST CORNER OF THE FORECAST AREA.
HAVE NON-DIURNAL TEMPERATURE TREND MENTIONED ACROSS THE NORTH AS
SHOULD SEE THE CAA DEVELOP LATE THIS MORNING AND INCREASE THROUGH
THE AFTERNOON. 850MB TEMPS DROP TO +4C TO +6C BY 18Z IN THE NORTH.
GUSTY NORTH TO NORTHWEST WINDS BEHIND THE FRONT WITH WINDS ATOP THE
MIXED LAYER INCREASING TO AROUND 25 TO 30 KNOTS. MUCH DRIER AIR MASS
FILTERS INTO THE STATE AS WELL WITH SURFACE DEW POINTS DROPPING INTO
UPPER 30S AND LOWER 40S OVER THE NORTHWEST. RH VALUES DECREASE TO
NEAR 25 PERCENT ACROSS A SMALL WESTERN PORTION OF FORECAST AREA.
THOUGH AN INCREASED FIRE WEATHER DANGER TODAY...HELD OFF ON RED FLAG
WARNING DUE TO CRITERIA NOT BEING MET WIDESPREAD.
.LONG TERM /TONIGHT THROUGH SATURDAY/...
ISSUED AT 343 AM CDT MON APR 21 2014
EARLY IN THE PERIOD...FEW CONCERNS. SYSTEM ON THE WAY OUT BY 00Z
TONIGHT WITH SECONDARY COLD FRONT NOW OVER NORTHERN MN DROPPING
SOUTHEAST ACROSS THE REGION TONIGHT...BRINGING DRIER AND COOLER AIR
INTO THE REGION BY MORNING. DESPITE WARM TEMPS THE PAST FEW DAYS...
MORNING LOWS TONIGHT WILL BE MUCH COOLER WITH MID 30S NORTH TO MID
40S SOUTH. TUESDAY LOOKS LIKE A NICE DAY WITH GENERALLY SUNNY SKIES
AND A FEW FAIR WX CUMULUS DURING THE MID AFTERNOON AS HIGH PRESSURE
DROPS SOUTHEAST THROUGH THE DAY...KEEPING WINDS LIGHT. LITTLE MIXING
TO PROMOTE MUCH WARMING OTHER THAN SUNSHINE...SO WILL STICK WITH
HIGHS IN THE UPPER 50S NORTHEAST AND MID 60S ACROSS THE WEST. MODELS
DIFFER SLIGHTLY ON TIMING OF UPSTREAM WAVE AND EXPECTED WARM AIR
ADVECTION/CLOUDS AND APPROACHING SHOWERS FOR WED. OVERALL...INCREASE
IN CLOUDS EXPECTED LATE DAY WEST TUESDAY WITH SHOWERS NEARING THE
WESTERN BORDER BY 12Z. THOUGH THUNDER MORE LIKELY ACROSS THE HIGH
PLAINS AND NE...DRY AIR OVER IOWA WILL COOL AND DIMINISH INSTABILITY
WHEN INITIAL PUSH OF MOISTURE ARRIVES. MODELS SHOW LITTLE
INSTABILITY UNTIL AFTERNOON WED AND THAT AGAIN IS LESS THAN
YESTERDAYS SOLUTIONS. THUS...HAVE TRIMMED AREAL COVERAGE OF THUNDER
TO ISO WEST IN THE MORNING AND ISO EAST/SCT FAR WEST IN THE PM HOURS
WEDNESDAY WITH THE FIRST REAL SURGE OF THETAE ADVECTION. AS THE
SYSTEM CROSSES THE REGION...CONFIDENCE IN EVOLUTION OF SYSTEM HAS
LESSENED SLIGHTLY. MODELS CONTINUE TO HAVE GENERAL TRENDS SIMILAR...
BUT DETAILS DIFFER. OVERALL THE BETTER INSTABILITY WILL REMAIN WEST
OF THE AREA UNTIL NEARER 00Z THUR...THEN WEAKEN OVERNIGHT PRIOR TO
INCREASING AGAIN FROM LATE MORNING THUR THROUGH 00Z FRI. STILL SOME
CONCERNS ABOUT OVERNIGHT CONVECTION ACROSS SOUTH/CENTRAL SECTIONS
WED NIGHT AS SOME BULK SHEAR COULD AID SVR POTENTIAL. BOTH THE
00Z GFS AND THE 12Z/NEW 00Z EURO NOW SUGGEST THAT THE LOW WILL
TRACK NORTHEAST ACROSS IA NEARLY EXITING OUR FORECAST AREA BY
18Z THUR...KEEPING THE BEST INSTABILITY AND SVR POTENTIAL EAST OF
THE AREA BY THURSDAY AFTERNOON. FOR NOW...WILL CONTINUE TO MONITOR
POTENTIAL BUT OVERALL CHANCES WOULD REMAIN CONDITIONAL ON ANY
BETTER ALIGNMENT OF FORCING AND STRONGER INSTABILITY THURSDAY.
BEYOND THUR AFTERNOON...MORE UNCERTAINTY IS ARISING IN THE
REMAINDER OF THE FORECAST. MODELS HANDLING THE DEPARTURE OF THE
SYSTEM WITH DIFFERING SPEED THUR NIGHT AND FRIDAY DUE TO A
SECONDARY H500 SYSTEM OVER CENTRAL CANADA POTENTIALLY PHASING WITH
THE DEPARTING H500 LOW. BOTH THE GEM/EURO TAKE THE FIRST SYSTEM
EAST QUICKLY ENOUGH TO PREVENT MUCH PHASING WHILE THE GFS HOLDS ON
TO A TROUGH EXTENDING WEST INTO MN. THIS RESULTS IN A FARTHER WEST
RIDGE AXIS OVER CANADA THAT DROPS SOUTH INTO THE NORTHERN PLAINS
AND DRIVES THE JET STREAM FARTHER SOUTH...DIRECTLY NEXT WEEKENDS
STORM SOUTH OF IOWA. THE GEM/EURO SHOW ONLY A SLIGHT DELAY IN
TIMING AND STILL BRING RAIN BACK INTO THE AREA FOR THE WEEKEND.
FOR NOW THE GFS SHOWS TOO DRASTIC A CHANGE FOR SUCH A SMALL H500
FEATURE. DUE TO UNCERTAINTY...WILL CUT BACK ON POP CHANCE AT ONSET
OF PRECIP EVENT NEXT SATURDAY BUT WILL STILL KEEP POP INCREASING
WITH TIME THROUGH SUNDAY. TEMPS WILL HAVE EVEN GREATER UNCERTAINTY
NOW...AS TIED TO CHANGES IN EVOLUTION AND TRACK OF WEEKEND UPPER
AIR PATTERN AND STORM TRACK. NEWEST 21/00Z EURO STILL KEEPS TREND
OF WET WEATHER NEXT WEEKEND...WHILE THE GFS REMAINS DRY. OVERALL
THE EURO TENDS TO PERFORM MORE CONSISTENTLY AFTER FCST 120 HOURS
SO WILL LEAN TOWARD GEM/EURO SOLUTIONS OF WETTER WEATHER SAT/SUN.
AS MENTIONED IN PREVIOUS NIGHTS AFDS...THERE IS A CONSISTENT
SIGNAL OF ENERGY STRETCHING FROM THE NORTH CENTRAL PACIFIC EAST TO
THE PLAINS...WHICH WOULD FAVOR INCLEMENT WEATHER HERE.
&&
.AVIATION...21/06Z
ISSUED AT 1129 PM CDT SUN APR 20 2014
SHRA AND TSRA HAVE FORMED NEAR BOUNDARY ACROSS NORTHERN IOWA AND
WILL CONTINUE TO AFFECT NORTHERN SITES KMCW/KALO/KFOD BEFORE
SLOWLY PUSHING SOUTH OVERNIGHT...REACHING KDSM NEAR 12Z AND KOTM
AFTER. CEILINGS AND VISIBILITIES WILL REMAIN PRIMARILY
VFR...THOUGH MAY BRIEFLY DROP TO MVFR OR LOWER WITH TSRA. WINDS
WILL BE FROM THE SOUTHWEST AHEAD OF BOUNDARY...MORE VARIABLE NEAR
BOUNDARY AND FROM THE NORTHWEST BEHIND BOUNDARY. WINDS WILL ALSO
BECOME GUSTY DURING THE DAY MONDAY BEFORE DIMINISHING NEAR SUNSET.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...PODRAZIK
LONG TERM...REV
AVIATION...AWB
AREA FORECAST DISCUSSION...corrected
NWS DODGE CITY KS
415 AM CDT Mon Apr 21 2014
...UDATED LONG TERM AND FIRE WEATHER SECTIONS...
.SHORT TERM...(Today and tonight)
ISSUED AT 317 AM CDT MON APR 21 2014
The main shortwave trough is depicted by the models to move into
eastern Kansas this morning. The RUC model has picked up on the MCV
over central Kansas and moves it southward into northwest Oklahoma
today in the northwesterly flow on the backside of the trough. Model
soundings show instability around 600-800 j/kg of CAPE as a mid
level cold pool moves southeast across western Kansas today. Given
the forcing with the MCV and a nearly uncapped sounding profile this
afternoon over south central Kansas, will add some slight chance
pops for showers and isolated thunder to the forecast.
Things will quiet down fairly quickly late this afternoon and early
evening as a ridge of surface high pressure moves east through the
High Plains. Winds will become light and variable in the evening and
gradually swing around to the southeast and south. Overnight lows
will be the coolest over central Kansas where low to mid 40s are
expected. Lows will drop into the upper 40s to around 50 along the
Colorado border where increasing southerly winds will help keep
temperatures up a few degrees more.
.LONG TERM...(Tuesday through Sunday)
ISSUED AT 414 AM CDT MON APR 21 2014
An upper ridge will be transitioning eastward across the Great
Plains on Tuesday. Surface pressure falls along the lee of the
Rockies and the retreating surface high pressure across the Missouri
valley will create a moisture transport zone over the central High
Plains, effectively causing an increasing in surface and 850 mb dew
points across western and central Kansas. Afternoon heating across
the higher terrain around the Palmer Divide will allow thunderstorms
to form and be steered eastward into this moisture and instability
axis. Some thunderstorms could move into western Kansas through the
evening hours most likely around Syracuse. With a lack of dynamics,
convection should be mainly diurnally driven, and as a result dry
weather is likely through the overnight Tuesday into Wednesday
morning with mild lows. An upper wave will be approaching the
region Wednesday with several impacts. A decent surface pressure
gradient will be in place as much drier air mixes out eastward
though the morning and afternoon. The overall momentum transfer will
probably be negatively influenced by mid level cloud decks indicated
on model soundings and may even prevent a high wind event given 0-1
km mean winds on the order of 35-40 knots. Additionally a set up for
severe storms will exist along and ahead of the dryline as the
atmosphere destabilizes through the morning. Potential for rotating
supercells exist with NAM model suggesting around 2-3 m2/s2 EHI(3km)
with up to round 2000 J/kg of surface based CAPE ahead of the
dryline feature. Good subsidence should follow in behind this
dryline overnight into Thursday morning. Dry and warm conditions
will likely follow into Friday as the next flat upper ridge settle
across the region. Additional thunderstorm chances are in the
forecast later in the weekend and early nextweek associated with
yet another west coast jet carving a trough into the southern
Rockies by the GFS and ECMWF.
&&
.AVIATION...(For the 06Z TAFS through 06Z Monday night)
ISSUED AT 1257 AM CDT MON APR 21 2014
Low level moisture advecting up into southwest Kansas could result
in 2-4 miles in mist along with IFR stratus. There is some
uncertainty as to how widespread it will become. For now will have
a tempo group for lower visibility at Garden City and Dodge City
early this morning with conditions improving to VFR between 10 and
12z. A cold front will move through around sunrise and sweep the
low level moisture out of the area. By this afternoon, some
instability showers could develop in the area around and east of
Dodge City and have added VCSH to the Dodge City TAF for this.
&&
.FIRE WEATHER...
ISSUED AT 414 AM CDT MON APR 21 2014
Elevated fire danger is expected for Tuesday as breezy southerly
winds and dew points in the 20s prevail through the day. A more
significant risk is expected Wednesday as a dryline moves as far
east as highway 283 by afternoon with strong gusty surface winds.
Fire weather watches and eventually red flag warningS may be issued
in the coming forecast shifts especially for areas west of Highway
83 for Wednesday.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 76 44 79 56 / 10 0 10 20
GCK 75 44 82 57 / 0 0 10 10
EHA 74 50 83 57 / 0 0 10 10
LBL 76 46 83 57 / 0 0 10 10
HYS 75 42 79 55 / 10 0 10 20
P28 76 46 79 54 / 20 0 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Gerard
LONG TERM...Russell
AVIATION...Gerard
FIRE WEATHER...Russell
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
318 AM CDT Mon Apr 21 2014
...Updated synopsis and short term discussion...
.SYNOPSIS...
ISSUED AT 317 AM CDT MON APR 21 2014
The 00z upper air analysis showed a shortwave trough extending from
southern Nebraska across southwest Kansas into the Texas Panhandle.
With fairly light steering flow aloft, this trough was slowly moving
eastward through the High Plains this morning. Thunderstorms over
central and western Kansas that had fired up Sunday afternoon had
pretty much dissipated early this morning. There were a few showers
over central Kansas around Hays and Lacrosse which were associated
with an MCV leftover from the thunderstorm complex earlier in the
evening.
&&
.SHORT TERM...(Today and tonight)
ISSUED AT 317 AM CDT MON APR 21 2014
The main shortwave trough is depicted by the models to move into
eastern Kansas this morning. The RUC model has picked up on the MCV
over central Kansas and moves it southward into northwest Oklahoma
today in the northwesterly flow on the backside of the trough. Model
soundings show instability around 600-800 j/kg of CAPE as a mid
level cold pool moves southeast across western Kansas today. Given
the forcing with the MCV and a nearly uncapped sounding profile this
afternoon over south central Kansas, will add some slight chance
pops for showers and isolated thunder to the forecast.
Things will quiet down fairly quickly late this afternoon and early
evening as a ridge of surface high pressure moves east through the
High Plains. Winds will become light and variable in the evening and
gradually swing around to the southeast and south. Overnight lows
will be the coolest over central Kansas where low to mid 40s are
expected. Lows will drop into the upper 40s to around 50 along the
Colorado border where increasing southerly winds will help keep
temperatures up a few degrees more.
.LONG TERM...(Monday night through Sunday)
ISSUED AT 149 PM CDT SUN APR 20 2014
Upper level ridging builds over the Plains Monday night through
Tuesday with dry conditions in the mid levels. This will allow
mostly clear skies to be observed across western Kansas. This will
be short lived as the next storm system moves into the Northern
Rockies Tuesday night into Wednesday. Southerly winds will be felt
across western Kansas as this system approaches with increasing mid
level moisture Tuesday night. A moderate upper level jet will be
found above western Kansas on Wednesday enhancing lift across the
area. Southerly winds will continue at the surface becoming windy in
the afternoon. In addition, a dryline is suggested to develop in the
afternoon with CAPE and shear increasing as the day progresses.
These conditions will bring a chance of thunderstorms ahead of the
dryline from late afternoon into Wednesday night. A few of these
storms could become strong to severe with large hail and damaging
winds being the main concern. A cold front then moves through
western Kansas Thursday morning shifting winds to the north. Lows
Tuesday morning will be in the low to mid 40s with highs Tuesday
reaching into the upper 70s and lower 80s. The warmest day of the
week looks to be on Wednesday with lows in the mid 50s and highs in
the lower 80s. Lows Thursday morning look to range from the mid 40s
across west central Kansas where the aforementioned cold front is
expected to move through early to upper 50s across south central
Kansas where the front is not expected to move through by sunrise.
Dry conditions are then expected during the remainder of the week as
an upper level ridge builds above the Plains with dry conditions in
the mid levels. Winds shift back to the south by Saturday as the
next storm system entered the western United States. This system is
expected to affect western Kansas this weekend bringing an increase
in clouds and a chance of thunderstorms. Highs Thursday through this
weekend will generally be in the 70s with lower 80s possible across
far southwestern Kansas on Saturday. Lows will generally be in the
mid to upper 40s Friday and Saturday morning.
&&
.AVIATION...(For the 06Z TAFS through 06Z Monday night)
ISSUED AT 1257 AM CDT MON APR 21 2014
Low level moisture advecting up into southwest Kansas could result
in 2-4 miles in mist along with IFR stratus. There is some
uncertainty as to how widespread it will become. For now will have
a tempo group for lower visibility at Garden City and Dodge City
early this morning with conditions improving to VFR between 10 and
12z. A cold front will move through around sunrise and sweep the
low level moisture out of the area. By this afternoon, some
instability showers could develop in the area around and east of
Dodge City and have added VCSH to the Dodge City TAF for this.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 76 44 79 56 / 10 0 10 20
GCK 75 44 82 57 / 0 0 10 10
EHA 74 50 83 57 / 0 0 10 10
LBL 76 46 83 57 / 0 0 10 10
HYS 75 42 79 55 / 10 0 10 20
P28 76 46 79 54 / 20 0 10 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...Gerard
SHORT TERM...Gerard
LONG TERM...Hovorka_42
AVIATION...Gerard
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1257 AM CDT Mon Apr 21 2014
...Updated aviation discussion...
.SHORT TERM...(This evening through Monday)
ISSUED AT 116 PM CDT SUN APR 20 2014
Ample insolation early this afternoon resulted in surface-based CAPE
in the 700-1100 J/kg west of Highway 283 to the Colorado border.
Lack of a capping inversion beneath cool temperatures in the
700-500mb layer (+2C at 700mb). There were two areas of surface
convergence that will support development of thunderstorms by
mid-afternoon. The first area is near the Colorado border along the
stationary trough axis, which is also near where the mid level
vorticity center is. We are also watching a secondary area of
interest from Dodge City south to the Oklahoma border where surface
wind convergence was slightly enhanced. 1km visible satellite
confirmed development of cumulus in both of these areas. Given the
higher degree of instability than earlier anticipated, a few hail
storms may occur with the largest hail most likely being around
1-inch in diameter (Quarter size). Severe weather threat will likely
wane after 00Z or so as showers and thunderstorms grow upscale. This
is what the HRRR would seem to suggest in its latest runs, which
makes sense given the marginal instability. Much of the
precipitation should be coming to an end/or exiting the southwest
Kansas region in the 04-07Z time frame so POPs will be lowered
during this time frame and shortly thereafter.
A northern stream shortwave trough will aid in bringing a cold front
south through western Nebraska late tonight, reaching southwestern
Kansas by mid to late morning Monday. The front is not expected to
have any impact on temperatures, though, so the going forecast of
upper 70s to near 80 still looks pretty good (especially along/south
of the Arkansas River).
.LONG TERM...(Monday night through Sunday)
ISSUED AT 149 PM CDT SUN APR 20 2014
Upper level ridging builds over the Plains Monday night through
Tuesday with dry conditions in the mid levels. This will allow
mostly clear skies to be observed across western Kansas. This will
be short lived as the next storm system moves into the Northern
Rockies Tuesday night into Wednesday. Southerly winds will be felt
across western Kansas as this system approaches with increasing mid
level moisture Tuesday night. A moderate upper level jet will be
found above western Kansas on Wednesday enhancing lift across the
area. Southerly winds will continue at the surface becoming windy in
the afternoon. In addition, a dryline is suggested to develop in the
afternoon with CAPE and shear increasing as the day progresses.
These conditions will bring a chance of thunderstorms ahead of the
dryline from late afternoon into Wednesday night. A few of these
storms could become strong to severe with large hail and damaging
winds being the main concern. A cold front then moves through
western Kansas Thursday morning shifting winds to the north. Lows
Tuesday morning will be in the low to mid 40s with highs Tuesday
reaching into the upper 70s and lower 80s. The warmest day of the
week looks to be on Wednesday with lows in the mid 50s and highs in
the lower 80s. Lows Thursday morning look to range from the mid 40s
across west central Kansas where the aforementioned cold front is
expected to move through early to upper 50s across south central
Kansas where the front is not expected to move through by sunrise.
Dry conditions are then expected during the remainder of the week as
an upper level ridge builds above the Plains with dry conditions in
the mid levels. Winds shift back to the south by Saturday as the
next storm system entered the western United States. This system is
expected to affect western Kansas this weekend bringing an increase
in clouds and a chance of thunderstorms. Highs Thursday through this
weekend will generally be in the 70s with lower 80s possible across
far southwestern Kansas on Saturday. Lows will generally be in the
mid to upper 40s Friday and Saturday morning.
&&
.AVIATION...(For the 06Z TAFS through 06Z Monday night)
ISSUED AT 1257 AM CDT MON APR 21 2014
Low level moisture advecting up into southwest Kansas could result
in 2-4 miles in mist along with IFR stratus. There is some
uncertainty as to how widespread it will become. For now will have
a tempo group for lower visibility at Garden City and Dodge City
early this morning with conditions improving to VFR between 10 and
12z. A cold front will move through around sunrise and sweep the
low level moisture out of the area. By this afternoon, some
instability showers could develop in the area around and east of
Dodge City and have added VCSH to the Dodge City TAF for this.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 45 79 56 84 / 0 10 20 40
GCK 43 82 57 83 / 0 10 10 30
EHA 46 83 57 84 / 0 10 10 20
LBL 46 83 57 85 / 0 10 10 30
HYS 43 79 55 82 / 0 10 20 50
P28 47 79 54 82 / 0 10 10 50
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Umscheid
LONG TERM...Hovorka_42
AVIATION...Gerard
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
544 AM EDT MON APR 21 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 424 AM EDT MON APR 21 2014
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW A SPLIT FLOW
REGIME ACRS THE CONUS WITH A STRONGER W-E POLAR BRANCH FLOW NEAR THE
CNDN BORDER TO THE N OF A WEAKER SRN BRANCH OVER THE SCENTRAL
STATES. SHRTWV RDG EMBEDDED IN THE POLAR BRANCH AND OVER NE MN/NW
ONTARIO AS WELL AS VERY DRY AIR SHOWN ON THE 00Z INL/MPX RAOBS ARE
BRINGING DRY WX TO UPR MI THIS MRNG EXCEPT OVER FAR SRN MENOMINEE
COUNTY...WHERE SOME ISOLD -SHRA ARE STILL PRESENT ON THE NRN EDGE OF
RIBBON OF DEEPER MSTR STRUNG W-E THRU THE CENTRAL LKS AND SAMPLED BY
THE FAIRLY MOIST 00Z GRB RAOB. MORE WDSPRD SHRA/EMBEDDED TS ARE
PRESENT OVER SW WI/FAR SE MN UNDER DEEPER MSTR/SOME UPR DVGC AHEAD
OF DISTURBANCE ON THE NRN EDGE OF SRN BRANCH FLOW. ALTHOUGH COLDER
CLOUD TOPS ARE EXPANDING TOWARD THE WI BORDER TO THE NE OF THESE
SHOWERS...THE LOWER LVL W FLOW OF VERY DRY AIR FM THE DIRECTION OF
MPX IS LIMITING THE N SPREAD OF THE SHRA LOCATED JUST S OF THAT RAOB
SITE. OTRW...SOME LOCALLY DENSE FOG HAS FORMED OVER THE CENTRAL/ERN
CWA AS THE DRIER AIR ALOFT MOVED OVER LOCATIONS THAT DID NOT SEE
SGNFT LLVL DRYING YDAY AFTN. OVER THE W WHERE SFC DEWPTS MIXED OUT
AS LO AS 25-30 AT IWD ON SUN AND TEMPS ARE STILL ABV 32 AT MOST
SPOTS...THERE IS LTL IF ANY FOG. A MUCH STRONGER SHRTWV IN THE POLAR
BRANCH FLOW IS NEAR LK WINNIPEG AND MOVING STEADILY TO THE E. THERE
HAVE BEEN SOME SHOWERS AND EVEN SOME LGT STRIKES IN MANITOBA RIGHT
UNDER THE STEEPER LAPSE RATES CLOSE TO THE CORE OF THIS DISTURBANCE.
BUT SINCE THIS SHRTWV IS CUTOFF FM THE MOISTER AIRMASS TO THE S...
THERE IS ONLY A NARROW BAND OF LIGHT SHOWERS ALONG ITS ATTENDANT
COLD FNT MOVING THRU NW MN EARLY THIS MRNG.
MAIN FCST CONCERNS IN THE SHORT TERM INVOLVE FOG EARLY THIS MRNG AND
THEN PCPN CHCS LATER TODAY/TNGT AS POLAR BRANCH SHRTWV/ATTENDANT
COLD FNT IMPACT UPR MI.
TODAY...EXPECT LOCALLY DENSE FOG TO PERSIST EARLY THIS MRNG OVER THE
SE HALF OF THE CWA...BUT INCRSG HI CLDS SHOULD LIMIT THE POTENTIAL
FOR WDSPRD DENSE FOG. WL ISSUE AN SPS TO ALERT THE PUBLIC TO LOCALLY
REDUCED VSBYS. SHRTWV NEAR LK WINNIPEG IS FCST TO MOVE E THRU NW
ONTARIO AND DRAG IT ATTENDANT COLD FNT ACRS UPR MI THIS AFTN. SINCE
BULK OF DPVA/DEEP LYR QVECTOR CNVGC WL REMAIN TO THE N AND JUST
BRUSH THE NRN LAND CWA...SUSPECT ONLY ISOLD-SCT SHOWERS WL ACCOMPANY
THE FROPA. ALMOST ALL THE MODELS THAT WERE SHOWING A GREATER
INTERACTION BTWN THIS SHRTWV/DEEPER MSTR TO THE S AND SGNFT
EXPANSION OF THIS MSTR/SHOWERS INTO UPR MI HAVE RETREATED A BIT FM
THIS FCST...A REASONABLE TREND CONSIDERING THE VERY DRY NATURE OF
THE 00Z MPX RAOB AND LACK OF SGNFT BACKING OF THE UPR FLOW FM THE W
THRU THE DAY. THE 00Z HI RES CNDN MODEL SHOWS THE HEAVIER PCPN
OVERSPREADING MOST OF UPR MI ALONG WITH THE MOST UNSTABLE MIXED LYR
CAPES AOA 1000 J/KG. FCST SDNGS FM THIS MODEL SHOW FAIRLY IMPRESSIVE
MOISTENING THRU THE LOWER TROP WITH SFC DEWPTS RISING TO ARND
55...WHICH DOES NOT SEEM RSNBL IN THE ABSENCE OF A DEEPER SW FLOW.
THE 00Z NAM SHOWS MORE MODEST MOISTENING/DESTABILIZATION OVER THE
SCENTRL. WL CARRY THE HIER CHC POPS THIS AFTN WHERE THIS MODEL SHOWS
THE GREATER INSTABILITY UP TO 700-800 J/KG OVER THE SCNTRL. INCLUDED
A SCHC OF TS IN THIS AREA AS WELL GIVEN ARRIVAL OF COLD FNT DURING
PEAK HEATING TIME THAT WL PUSH TEMPS WELL ABV NORMAL AGAIN IN THE
PRESENCE OF H85 TEMPS NOT FAR FM 10C AND AWAY FM THE MODERATING
INFLUENCE OF THE LKS. COOLER AIR WL ARRIVE OVER THE W LATER IN THE
DAY FOLLOWING THE FROPA.
TNGT...NW FLOW WITH H925 WINDS UP TO 25-35 KTS IN THE WAKE OF THE
COLD FROPA WL DRIVE COLDER AIR BACK INTO THE UPR LKS TNGT. MODELS
SHOW H85 TEMPS SINKING AS LO AS -7 TO -8C OVER THE W BY 12Z TUE.
WHILE THIS INCOMING AIRMASS WL NOT BE COLD ENUF FOR LK EFFECT
PCPN...MODELS DO SHOW SOME LLVL MOISTENING BLO STRENGTHENING
SUBSIDENCE INVRN ARND H85 UNDER THE LARGE SCALE QVECTOR DVGC LEFT IN
THE WAKE OF DEPARTING SHRTWV. GOING FCST SHOWS SOME DRIZZLE/FRZG
DRIZZLE OVER THE HIER TERRAIN WITH MOISTENING/INVRN BASE BLO THE
DGZ. THIS FCST SEEMS RSNBL...BUT DID ADD SOME FLURRIES AS WELL.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 543 AM EDT MON APR 21 2014
SFC TEMPS SHOULD WARM QUICKLY TUESDAY MORNING...LIMITING THE
POTENTIAL FOR FREEZING DRIZZLE. WILL STILL KEEP DRIZZLE GOING GIVEN
THE LIMITED LIKELIHOOD OF ICE CRYSTALS IN THE SOUNDING. OTHERWISE
COOL N-NW WINDS WILL BE THE RULE...WITH 850MB TEMPS IN THE -6 TO -8C
RANGE HELPING TO KEEP MAX SFC TEMPS TUESDAY IN THE UPPER 30S TO MID
40S OVER MUCH OF THE CWA.
DRY HIGH PRESSURE OVERHEAD TUESDAY NIGHT INTO WEDNESDAY WILL RESULT
IN NEARLY CALM WINDS WEDNESDAY MORNING. WITH FEW IF ANY CLOUDS
AROUND AND PW VALUES FALLING TO AROUND 45 PERCENT OF NORMAL /0.25IN/
SHOULD ALLOW TEMPS TO FALL INTO THE 20S TUESDAY NIGHT/WEDNESDAY
MORNING.
PLENTY OF UNCERTAINTY REMAINS WITH OUR END OF THE WEEK SYSTEM. WHILE
POPS HAVE BEEN INCREASED AND MUCH OF THE FOCUS FOR MODERATE TO HEAVY
PRECIP REMAINS OVER THE W HALF OF UPPER MI...THE 21/00Z RUN OF THE
ECMWF HAS BACKED AWAY FROM THE DEEPER MORE WRAPPED UP SFC LOW THAT
IT/S 20/12Z RUN INDICATED. STILL...ALL INDICATIONS ARE THAT 0.5-1IN
OF LIQUID WILL BE POSSIBLE NEAR AND W OF A LINE FROM MQT TO MNM
THURSDAY INTO THURSDAY NIGHT. THE ECMWF ENSEMBLES HAVE 30-40 PERCENT
CHANCE OF SEEING 1IN OR MORE OVER THE W HALF. GIVEN THAT MUCH OF THE
SYSTEM IS AROUND 84HRS OR MORE INTO THE FUTURE...WILL CONTINUE WITH
A MORE BROAD/AVERAGED SOLUTION AT THIS POINT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 122 AM EDT MON APR 21 2014
THE BIG FCST CONCERN OVERNIGHT WILL BE FOG...ESPECIALLY AT KSAW
WHERE DEWPOINTS REMAIN MOIST (IN THE LOWER 40S). HAVE
FOLLOWED MOS GUIDANCE FOR MUCH OF THE TIMING ON THE FOG AND
INTENSITY. KIWD MAY NOT SEE MUCH FOG TONIGHT AS LIGHT DOWNSLOPING
SOUTHEAST WINDS WILL LIKELY LIMIT FOG POTENTIAL. THE CONCERN AT
KCMX IS WHETHER DRIER AIR OVER LAKE SUPERIOR MAY LIMIT FOG POTENTIAL
DESPITE WEAK UPSLOPE EAST FLOW DEVELOPING LATE TONIGHT. SINCE THE
DEWPOINT DEPRESSION AT KCMX IS ONLY 2F STILL THINK PREVAILING IFR
VBSY IS A GOOD BET FOR THE 07-14Z TIME FRAME. KSAW SHOULD HAVE THE
BEST OPPORTUNITY TO FALL TO LIFR/PERHAPS VLIFR/BLO LANDING MINS BASED
ON LOWER 40S DEWPOINTS AND LIGHT SOUTH-SOUTHEAST UPSLOPE FLOW
DEVELOPING OVERNIGHT UNDER GENERALLY CLEAR SKIES. EXPECT THE FOG TO
BURN OFF DURING THE MORNING AS MIXING INCREASES AND SOME MID CLOUDS
APPROACH TOWARDS AFTERNOON. WINDS WILL SHIFT WESTERLY BEHIND
TROUGH/FRONTAL PASSAGE.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 424 AM EDT MON APR 21 2014
LIGHT WINDS UNDER 15 KTS THIS MORNING ASSOCIATED WITH WEAK HIGH
PRESSURE RIDGE WILL SHIFT TO THE NW LATE TODAY/THIS EVENING
FOLLOWING A COLD FRONTAL PASSAGE AND INCREASE UP TO 25-30 KTS
TONIGHT AS MUCH COLDER AIR INVADES THE UPPER LAKES. NOT OUT OF THE
QUESTION THERE COULD BE SOME GALES OVER PORTIONS OF THE EAST HALF OF
THE LAKE UNDER THE SHARPER GRADIENT/STRONGEST LOW LEVEL WINDS.
MENTIONED SOME GALE FORCE GUSTS UP TO 35 KTS OVER THE ECENTRAL FOR
NOW. THESE STONG WINDS WILL DIMINISH TUE THRU WED AS A HI PRES RIDGE
AND WEAKER PRES GRADIENT MOVE OVER THE AREA. AS ANOTHER LOW PRESSURE
SYSTEM APPROACHES FROM THE PLAINS LATER IN THE WEEK AND THE GRADIENT
SHARPENS AGAIN...INCREASING SE WINDS WILL SHIFT TO THE NE. DEPENDING
ON THE TRACK AND INTENSITY OF THIS LO...THERE COULD BE AT LEAST A
PERIOD OF GALE FORCE WINDS.
&&
.HYDROLOGY...
ISSUED AT 1202 AM EDT MON APR 21 2014
HIGHEST SNOW DEPTH REPORTED YESTERDAY MORNING OF 32IN AT MOHAWK WAS
ABLE TO DROP DOWN TO 28IN BY LATE EVENING. AT THE OTHER END OF THE
SPECTRUM...SEVERAL SITES FROM IWD THROUGH ISQ WERE REPORTING LITTLE
TO NO SNOW. TODAY WILL BE ANOTHER DAY OF MELTING...AS HIGH
TEMPERATURES JUMP INTO THE 50S AND LOW 60S FOR MUCH OF THE AREA. THE
MELT WILL SLOW TUESDAY-TUESDAY NIGHT OVER N UPPER MI AS COLD N-NNW
WINDS KEEP TEMPS TOPPING OUT IN THE 30S AND LOW 40S TUESDAY. AS FOR
FURTHER OUT...TEMPERATURES WILL RETURN TO NEAR NORMAL VALUES
TEMPORARILY WEDNESDAY BEFORE FALLING BACK INTO THE 30S AND 40S
THROUGH THE UPCOMING WEEKEND.
WILL CONTINUE TO NOTICE SIGNIFICANT STREAM/RIVER RISES OVER THE NEXT
FEW DAYS. UNSETTLED WEATHER WILL RETURN FROM THURSDAY THROUGH
FRIDAY...ADDING TO THE RUNOFF. AT THIS POINT THE BEST CHANCE OF
SIGNIFICANT PRECIPITATION LOOKS TO BE OVER THE W HALF OF UPPER
MI...AND SPECIFICALLY THE KEWEENAW PENINSULA WHERE 0.75-1IN OF
LIQUID WILL BE POSSIBLE BY FRIDAY AFTERNOON. WE WILL CONTINUE TO
REFINE THE FCST AS THE TIME NEARS.
SO FAR THE LOCATIONS EXPERIENCING SIGNIFICANT RISES HAVE BEEN
ALSTON/ALSM4/ ON THE STURGEON RIVER...ROCKLAND/RKLM4/ ON THE
ONTONAGON RIVER...AND TO A LESSER EXTENT THE HYDE/FRDM4/ ON THE FORD
RIVER.
WIDESPREAD FLOODING IS NOT FORESEEN AT THIS TIME. HOWEVER...ANY
RIVER THAT HAS ICE REMAINING ON IT...ESPECIALLY THE ESCANABA RIVER
IN DELTA COUNTY...COULD EXPERIENCE AN ICE JAM WITH THE RISING RIVER
LEVELS THIS WEEK. THOSE LIVING AROUND RIVERS...CREEKS...AND STREAMS
SHOULD MONITOR BOTH RIVER LEVELS AND ICE CONDITIONS. ICE JAMS CAN
FORM AND BREAK QUICKLY...RESULTING IN RAPIDLY FLUCTUATING RIVER
LEVELS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...KF
AVIATION...VOSS/KC
MARINE...KC
HYDROLOGY...KF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
425 AM EDT MON APR 21 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 424 AM EDT MON APR 21 2014
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW A SPLIT FLOW
REGIME ACRS THE CONUS WITH A STRONGER W-E POLAR BRANCH FLOW NEAR THE
CNDN BORDER TO THE N OF A WEAKER SRN BRANCH OVER THE SCENTRAL
STATES. SHRTWV RDG EMBEDDED IN THE POLAR BRANCH AND OVER NE MN/NW
ONTARIO AS WELL AS VERY DRY AIR SHOWN ON THE 00Z INL/MPX RAOBS ARE
BRINGING DRY WX TO UPR MI THIS MRNG EXCEPT OVER FAR SRN MENOMINEE
COUNTY...WHERE SOME ISOLD -SHRA ARE STILL PRESENT ON THE NRN EDGE OF
RIBBON OF DEEPER MSTR STRUNG W-E THRU THE CENTRAL LKS AND SAMPLED BY
THE FAIRLY MOIST 00Z GRB RAOB. MORE WDSPRD SHRA/EMBEDDED TS ARE
PRESENT OVER SW WI/FAR SE MN UNDER DEEPER MSTR/SOME UPR DVGC AHEAD
OF DISTURBANCE ON THE NRN EDGE OF SRN BRANCH FLOW. ALTHOUGH COLDER
CLOUD TOPS ARE EXPANDING TOWARD THE WI BORDER TO THE NE OF THESE
SHOWERS...THE LOWER LVL W FLOW OF VERY DRY AIR FM THE DIRECTION OF
MPX IS LIMITING THE N SPREAD OF THE SHRA LOCATED JUST S OF THAT RAOB
SITE. OTRW...SOME LOCALLY DENSE FOG HAS FORMED OVER THE CENTRAL/ERN
CWA AS THE DRIER AIR ALOFT MOVED OVER LOCATIONS THAT DID NOT SEE
SGNFT LLVL DRYING YDAY AFTN. OVER THE W WHERE SFC DEWPTS MIXED OUT
AS LO AS 25-30 AT IWD ON SUN AND TEMPS ARE STILL ABV 32 AT MOST
SPOTS...THERE IS LTL IF ANY FOG. A MUCH STRONGER SHRTWV IN THE POLAR
BRANCH FLOW IS NEAR LK WINNIPEG AND MOVING STEADILY TO THE E. THERE
HAVE BEEN SOME SHOWERS AND EVEN SOME LGT STRIKES IN MANITOBA RIGHT
UNDER THE STEEPER LAPSE RATES CLOSE TO THE CORE OF THIS DISTURBANCE.
BUT SINCE THIS SHRTWV IS CUTOFF FM THE MOISTER AIRMASS TO THE S...
THERE IS ONLY A NARROW BAND OF LIGHT SHOWERS ALONG ITS ATTENDANT
COLD FNT MOVING THRU NW MN EARLY THIS MRNG.
MAIN FCST CONCERNS IN THE SHORT TERM INVOLVE FOG EARLY THIS MRNG AND
THEN PCPN CHCS LATER TODAY/TNGT AS POLAR BRANCH SHRTWV/ATTENDANT
COLD FNT IMPACT UPR MI.
TODAY...EXPECT LOCALLY DENSE FOG TO PERSIST EARLY THIS MRNG OVER THE
SE HALF OF THE CWA...BUT INCRSG HI CLDS SHOULD LIMIT THE POTENTIAL
FOR WDSPRD DENSE FOG. WL ISSUE AN SPS TO ALERT THE PUBLIC TO LOCALLY
REDUCED VSBYS. SHRTWV NEAR LK WINNIPEG IS FCST TO MOVE E THRU NW
ONTARIO AND DRAG IT ATTENDANT COLD FNT ACRS UPR MI THIS AFTN. SINCE
BULK OF DPVA/DEEP LYR QVECTOR CNVGC WL REMAIN TO THE N AND JUST
BRUSH THE NRN LAND CWA...SUSPECT ONLY ISOLD-SCT SHOWERS WL ACCOMPANY
THE FROPA. ALMOST ALL THE MODELS THAT WERE SHOWING A GREATER
INTERACTION BTWN THIS SHRTWV/DEEPER MSTR TO THE S AND SGNFT
EXPANSION OF THIS MSTR/SHOWERS INTO UPR MI HAVE RETREATED A BIT FM
THIS FCST...A REASONABLE TREND CONSIDERING THE VERY DRY NATURE OF
THE 00Z MPX RAOB AND LACK OF SGNFT BACKING OF THE UPR FLOW FM THE W
THRU THE DAY. THE 00Z HI RES CNDN MODEL SHOWS THE HEAVIER PCPN
OVERSPREADING MOST OF UPR MI ALONG WITH THE MOST UNSTABLE MIXED LYR
CAPES AOA 1000 J/KG. FCST SDNGS FM THIS MODEL SHOW FAIRLY IMPRESSIVE
MOISTENING THRU THE LOWER TROP WITH SFC DEWPTS RISING TO ARND
55...WHICH DOES NOT SEEM RSNBL IN THE ABSENCE OF A DEEPER SW FLOW.
THE 00Z NAM SHOWS MORE MODEST MOISTENING/DESTABILIZATION OVER THE
SCENTRL. WL CARRY THE HIER CHC POPS THIS AFTN WHERE THIS MODEL SHOWS
THE GREATER INSTABILITY UP TO 700-800 J/KG OVER THE SCNTRL. INCLUDED
A SCHC OF TS IN THIS AREA AS WELL GIVEN ARRIVAL OF COLD FNT DURING
PEAK HEATING TIME THAT WL PUSH TEMPS WELL ABV NORMAL AGAIN IN THE
PRESENCE OF H85 TEMPS NOT FAR FM 10C AND AWAY FM THE MODERATING
INFLUENCE OF THE LKS. COOLER AIR WL ARRIVE OVER THE W LATER IN THE
DAY FOLLOWING THE FROPA.
TNGT...NW FLOW WITH H925 WINDS UP TO 25-35 KTS IN THE WAKE OF THE
COLD FROPA WL DRIVE COLDER AIR BACK INTO THE UPR LKS TNGT. MODELS
SHOW H85 TEMPS SINKING AS LO AS -7 TO -8C OVER THE W BY 12Z TUE.
WHILE THIS INCOMING AIRMASS WL NOT BE COLD ENUF FOR LK EFFECT
PCPN...MODELS DO SHOW SOME LLVL MOISTENING BLO STRENGTHENING
SUBSIDENCE INVRN ARND H85 UNDER THE LARGE SCALE QVECTOR DVGC LEFT IN
THE WAKE OF DEPARTING SHRTWV. GOING FCST SHOWS SOME DRIZZLE/FRZG
DRIZZLE OVER THE HIER TERRAIN WITH MOISTENING/INVRN BASE BLO THE
DGZ. THIS FCST SEEMS RSNBL...BUT DID ADD SOME FLURRIES AS WELL.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 438 PM EDT SUN APR 20 2014
A SERIES OF FAIRLY ENERGETIC SYSTEMS WILL TRACK ACROSS THE CONUS
OVER THE NEXT 7 TO 10 DAYS. GIVEN THE TIME OF YEAR...CAN`T RULE OUT
THE POSSIBILITY OF MID/UPPER LEVEL LOWS DEVELOPING/CLOSING OFF AND
SLOWING THE PROGRESSION DOWN. IF SO...DEPENDING ON WHERE IT
HAPPENS...SIGNIFICANT PCPN COULD BE IN THE OFFING ALONG WITH THE
POSSIBILITY OF LATE SEASON SNOW. AT THIS POINT...MEDIUM RANGE
GUIDANCE POINTS TOWARD A PROGRESSIVE PATTERN WITH THE FIRST
SHORTWAVE TROF PASSING ACROSS THE UPPER LAKES MON NIGHT. THIS WILL
BE FOLLOWED BY A MID/UPPER LEVEL RIDGE ARRIVING WED. ON ITS HEELS
WILL BE THE NEXT MORE POTENT SHORTWAVE TROF WHICH MOVES ONSHORE OVER
THE WRN CONUS TUE. BY THE TIME IT REACHES THE GREAT LAKES LATE IN
THE WORK WEEK...THIS SHORTWAVE TROF WILL HAVE INTERACTED WITH A NRN
STREAM WAVE DROPPING S THRU CNTRL CANADA. DEPENDING ON WHERE/WHEN
THE INTERACTION BTWN THE 2 WAVES OCCURS...PTYPE COULD BECOME MORE OF
AN ISSUE DURING THE PRIMARY PUSH OF PCPN ACROSS THE AREA. RIGHT
NOW...IT APPEARS RAIN WILL BE THE MAIN PTYPE. FEATURES INVOLVED
ARE CERTAINLY FAR ENOUGH OUT IN THE FCST CYCLE FOR IMPORTANT
ADJUSTMENTS TO OCCUR. IN ANY EVENT...THE INFUSION OF THE NRN STREAM
WAVE WILL RESULT IN A DUMP OF COLDER AIR/BLO NORMAL TEMPS LATE WEEK
INTO THE WEEKEND...INCLUDING AT LEAST SOME LIGHT SNOW ON THE
BACKSIDE OF THE LATE WEEK SYSTEM. BEYOND THIS 7 DAY FORECAST...
THERE ARE HINTS FLOW COULD BECOME QUITE BLOCKY ACROSS CANADA WHICH
MAY HOLD COOL AIR IN PLACE ACROSS MUCH OF THE NRN CONUS/SRN CANADA.
SO...TEMPS NEXT WEEK ARE MORE LIKELY TO BE IN THE NORMAL TO BLO
NORMAL RANGE RATHER THAN ABOVE NORMAL. KEEP IN MIND NORMALS NEXT
WEEK ARE GENERALLY 50S N TO LOW/MID 60S S.
BEGINNING MON NIGHT...COLD FRONT ASSOCIATED WITH SHORTWAVE PASSING
THRU THE UPPER LAKES WILL BE EXITING THE E IN THE EVENING. UNDER CAA
REGIME MON NIGHT...NAM/GFS INDICATE SIGNIFICANT LOW-LEVEL
MOISTENING...ESPECIALLY IN THE N/NNW WIND UPLSOPE AREAS...WHICH
RAISES THE PROSPECT FOR SOME -DZ/-FZDZ TO DEVELOP AS MOISTURE DOES
NOT EXTEND TO -10C ISOTHERM. LOW CONFIDENCE IF IT WILL HAPPEN... BUT
THE E WOULD BE MOST FAVORED.
AFTER SOME MORNING CLOUDS IN CYCLONIC FLOW AND THEN LIKELY A PERIOD
OF BKN CU DEVELOPMENT LATE MORNING THRU EARLY AFTN UNDER 850MB
THERMAL TROF...SKIES WILL CLEAR IN THE AFTN AS MUCH DRIER AIR MASS
SETTLES INTO THE AREA IN ASSOCIATION WITH SFC HIGH PRES RIDGE
SHIFTING INTO THE UPPER LAKES. N TO NW GRADIENT WIND AIDED BY LAKE
BREEZE COMPONENT WILL LEAD TO A CHILLY DAY ALONG LAKE SUPERIOR WITH
HIGH TEMPERATURES IN THE 30S. WELL INLAND...TEMPS SHOULD STILL RISE
WELL INTO THE 40S TO AROUND 50F UNDER LATE APR SUNSHINE.
IDEAL RADIATIONAL COOLING NIGHT SETS UP TUE NIGHT UNDER SFC HIGH
PRES AND CLEAR SKIES. PRECIPITABLE WATER OF 40-60PCT OF NORMAL WILL
AID THE COOLING PROCESS. FAVORED THE LOW END OF GUIDANCE...
ESPECIALLY WHERE DECENT SNOW COVER WILL STILL EXIST. TRADITIONAL
COLD SPOTS MAY SLIP INTO THE TEENS.
SFC HIGH PRES SLIPS E WED. ALTHOUGH 06Z GFS/00Z ECMWF SHOW PCPN
REACHING WRN UPPER MI LATE IN THE DAY WED ASSOCIATED WITH WEAK LEAD
SHORTWAVE CUTTING THRU MID/UPPER RIDGE WELL IN ADVANCE OF THE
AFOREMENTIONED LATE WEEK SYSTEM...WILL MAINTAIN DRY WEATHER THRU THE
AFTN AS EASTERLY LOW-LEVEL WIND COMPONENT EMANATING FROM DEPARTING
SFC HIGH SHOULD HELP HOLD LOW-LEVEL DRY AIR IN PLACE. 12Z RUNS HAVE
SLOWED EASTWARD PCPN PROGRESSION...SO DRY FCST SEEMS IN GOOD
SHAPE.
DESPITE COMPLEXITIES IN THE FLOW REGIME...MEDIUM RANGE GUIDANCE IS
IN GOOD AGREEMENT WITH THE SHORTWAVE TROF MOVING ONSHORE OVER THE W
COAST TUE AND REACHING THE GREAT LAKES FRI. WITH PUSH OF STRONGEST
WAA/ISENTROPIC ASCENT ARRIVING THU...HIGHEST POPS WILL BE USED AT
THAT TIME AS AN AREA OF RAIN WILL LIKELY MOVE ACROSS THE AREA.
GEM/ECMWF SHOW 850MB TEMPS HOVERING AROUND 0C WED NIGHT THRU THU ON
FRONT SIDE OF SYSTEM...BUT BOUNDARY LAYER SHOULD BE SUFFICIENTLY
WARM FOR ONLY RAIN GIVEN THAT IT`S LATE APR. STILL...IT WILL BE
SOMETHING TO MONITOR IN THE COMING DAYS DUE TO SOME UNCERTAINTY IN
THE NRN STREAM FLOW ACROSS CANADA AND THE INTERACTION IT HAS WITH
THE SHORTWAVE MOVING ACROSS THE CONUS. WOULDN`T TAKE MUCH OF
SOUTHWARD SHIFT OF SYSTEM TO RESULT IN ANOTHER LATE SEASON SNOW FOR
THE W AND N HIGHER TERRAIN. TODAYS 12Z ECMWF HAS TRENDED DEEPER WITH
THE MIDLEVEL LOW AS IT MOVES ACROSS THE UPPER LAKES THU NIGHT/FRI.
IF VALID...SOME ACCUMULATING SNOW WOULD BE POSSIBLE WITH DEFORMATION
PCPN SHIELD IMPACTING WRN AND NRN UPPER MI THU NIGHT/FRI.
ANY LINGERING PCPN WILL WIND DOWN/END SAT AS SYSTEM MOVES OFF TO THE
E. TEMPS SAT WILL BE WELL BLO NORMAL IN THE 30S N TO LOW/MID 40S
SCNTRL. ONLY SLIGHT MODERATION IS EXPECTED SUN AS SFC HIGH PRES
RIDGE NOSES INTO THE AREA.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 122 AM EDT MON APR 21 2014
THE BIG FCST CONCERN OVERNIGHT WILL BE FOG...ESPECIALLY AT KSAW
WHERE DEWPOINTS REMAIN MOIST (IN THE LOWER 40S). HAVE
FOLLOWED MOS GUIDANCE FOR MUCH OF THE TIMING ON THE FOG AND
INTENSITY. KIWD MAY NOT SEE MUCH FOG TONIGHT AS LIGHT DOWNSLOPING
SOUTHEAST WINDS WILL LIKELY LIMIT FOG POTENTIAL. THE CONCERN AT
KCMX IS WHETHER DRIER AIR OVER LAKE SUPERIOR MAY LIMIT FOG POTENTIAL
DESPITE WEAK UPSLOPE EAST FLOW DEVELOPING LATE TONIGHT. SINCE THE
DEWPOINT DEPRESSION AT KCMX IS ONLY 2F STILL THINK PREVAILING IFR
VBSY IS A GOOD BET FOR THE 07-14Z TIME FRAME. KSAW SHOULD HAVE THE
BEST OPPORTUNITY TO FALL TO LIFR/PERHAPS VLIFR/BLO LANDING MINS BASED
ON LOWER 40S DEWPOINTS AND LIGHT SOUTH-SOUTHEAST UPSLOPE FLOW
DEVELOPING OVERNIGHT UNDER GENERALLY CLEAR SKIES. EXPECT THE FOG TO
BURN OFF DURING THE MORNING AS MIXING INCREASES AND SOME MID CLOUDS
APPROACH TOWARDS AFTERNOON. WINDS WILL SHIFT WESTERLY BEHIND
TROUGH/FRONTAL PASSAGE.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 424 AM EDT MON APR 21 2014
LIGHT WINDS UNDER 15 KTS THIS MORNING ASSOCIATED WITH WEAK HIGH
PRESSURE RIDGE WILL SHIFT TO THE NW LATE TODAY/THIS EVENING
FOLLOWING A COLD FRONTAL PASSAGE AND INCREASE UP TO 25-30 KTS
TONIGHT AS MUCH COLDER AIR INVADES THE UPPER LAKES. NOT OUT OF THE
QUESTION THERE COULD BE SOME GALES OVER PORTIONS OF THE EAST HALF OF
THE LAKE UNDER THE SHARPER GRADIENT/STRONGEST LOW LEVEL WINDS.
MENTIONED SOME GALE FORCE GUSTS UP TO 35 KTS OVER THE ECENTRAL FOR
NOW. THESE STONG WINDS WILL DIMINISH TUE THRU WED AS A HI PRES RIDGE
AND WEAKER PRES GRADIENT MOVE OVER THE AREA. AS ANOTHER LOW PRESSURE
SYSTEM APPROACHES FROM THE PLAINS LATER IN THE WEEK AND THE GRADIENT
SHARPENS AGAIN...INCREASING SE WINDS WILL SHIFT TO THE NE. DEPENDING
ON THE TRACK AND INTENSITY OF THIS LO...THERE COULD BE AT LEAST A
PERIOD OF GALE FORCE WINDS.
&&
.HYDROLOGY...
ISSUED AT 1202 AM EDT MON APR 21 2014
HIGHEST SNOW DEPTH REPORTED YESTERDAY MORNING OF 32IN AT MOHAWK WAS
ABLE TO DROP DOWN TO 28IN BY LATE EVENING. AT THE OTHER END OF THE
SPECTRUM...SEVERAL SITES FROM IWD THROUGH ISQ WERE REPORTING LITTLE
TO NO SNOW. TODAY WILL BE ANOTHER DAY OF MELTING...AS HIGH
TEMPERATURES JUMP INTO THE 50S AND LOW 60S FOR MUCH OF THE AREA. THE
MELT WILL SLOW TUESDAY-TUESDAY NIGHT OVER N UPPER MI AS COLD N-NNW
WINDS KEEP TEMPS TOPPING OUT IN THE 30S AND LOW 40S TUESDAY. AS FOR
FURTHER OUT...TEMPERATURES WILL RETURN TO NEAR NORMAL VALUES
TEMPORARILY WEDNESDAY BEFORE FALLING BACK INTO THE 30S AND 40S
THROUGH THE UPCOMING WEEKEND.
WILL CONTINUE TO NOTICE SIGNIFICANT STREAM/RIVER RISES OVER THE NEXT
FEW DAYS. UNSETTLED WEATHER WILL RETURN FROM THURSDAY THROUGH
FRIDAY...ADDING TO THE RUNOFF. AT THIS POINT THE BEST CHANCE OF
SIGNIFICANT PRECIPITATION LOOKS TO BE OVER THE W HALF OF UPPER
MI...AND SPECIFICALLY THE KEWEENAW PENINSULA WHERE 0.75-1IN OF
LIQUID WILL BE POSSIBLE BY FRIDAY AFTERNOON. WE WILL CONTINUE TO
REFINE THE FCST AS THE TIME NEARS.
SO FAR THE LOCATIONS EXPERIENCING SIGNIFICANT RISES HAVE BEEN
ALSTON/ALSM4/ ON THE STURGEON RIVER...ROCKLAND/RKLM4/ ON THE
ONTONAGON RIVER...AND TO A LESSER EXTENT THE HYDE/FRDM4/ ON THE FORD
RIVER.
WIDESPREAD FLOODING IS NOT FORESEEN AT THIS TIME. HOWEVER...ANY
RIVER THAT HAS ICE REMAINING ON IT...ESPECIALLY THE ESCANABA RIVER
IN DELTA COUNTY...COULD EXPERIENCE AN ICE JAM WITH THE RISING RIVER
LEVELS THIS WEEK. THOSE LIVING AROUND RIVERS...CREEKS...AND STREAMS
SHOULD MONITOR BOTH RIVER LEVELS AND ICE CONDITIONS. ICE JAMS CAN
FORM AND BREAK QUICKLY...RESULTING IN RAPIDLY FLUCTUATING RIVER
LEVELS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...ROLFSON
AVIATION...VOSS/KC
MARINE...KC
HYDROLOGY...KF
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1223 AM CDT MON APR 21 2014
.UPDATE...
ISSUED AT 1217 AM CDT MON APR 21 2014
JUST A SHORT UPDATE EARLIER TO ADJUST PRECIPITATION CHANCES FOR
THE REGION OVERNIGHT. ONE AREA WILL LINGER OVER NORTHERN KANSAS
WHERE THE MID LEVEL LOW WILL SLOWING CHURN EAST/SOUTHEAST. THIS
AREA WILL SEE THE MOST EFFICIENT AND HEAVIER RAINFALL TONIGHT.
SECOND AREA OF SHOWERS/ISOLATED STORMS IS ALONG THE ADVANCING
FRONT MOVING INTO VALLEY COUNTY. EXPECTING THESE SHOWERS AND
ISOLATED STORMS TO BE MOST NUMEROUS ACROSS THE NORTH THE NEXT
FEW HOURS BUT GRADUALLY LESSEN IN COVERAGE AS THEY APPROACH
THE I-80 CORRIDOR PER HRRR MODEL TRENDS.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 324 PM CDT SUN APR 20 2014
...SPOTTY SHWRS WITH POSSIBLE THUNDER DIMINISH WITH SUNSET THEN
A BURST OF N WINDS TOMORROW MORNING WITH TEMPS REMAINING MILD...
ALOFT: SPLIT FLOW CONTINUED OVER THE CONUS...WITH FASTER MORE
PROGRESSIVE FLOW ALONG THE US-CANADIAN BORDER. THE SLOWER/WEAKER
SRN STREAM WAS OVER THE SRN USA. A NRN STREAM SHORTWAVE TROF WAS
OVER SASKATCHEWAN. THIS TROF WILL CONTINUE E INTO ONTARIO THRU
TOMORROW. MEANWHILE...A COMPACT LOW WAS OVER THE SRN PLAINS. IT
TOO WILL MOVE E ROUGHLY IN PHASE WITH THE NRN TROF. THE FLOW WILL
CONSOLIDATE TOMORROW AND BECOME NW AS A RIDGE ADVANCES THRU THE
WRN USA...AHEAD OF A TROF THAT WILL MOVE ONTO THE W COAST MON
NIGHT.
SURFACE: THE REMNANTS OF A COOL FRONT EXTENDED SW-NE FROM THE
SANDHILLS TO NEAR MCCOOK. A PACIFIC ORIGIN COOL FRONT WAS
PROGRESSING THRU THE NRN ROCKIES THIS AFTERNOON /ASSOCIATED WITH
THE SASK TROF/ AND WE JUST EMERGING INTO THE WRN DAKOTAS. THIS
FRONT WILL CROSS THE FCST AREA TONIGHT...BETWEEN MIDNIGHT AND
SUNRISE. NRN PLAINS HIGH PRES WILL BUILD IN TOMORROW.
THE REST OF THIS AFTERNOON: PARTLY-MOSTLY CLOUDY WITH SCATTERED
SHWRS AND TSTMS. THIS ACTIVITY WILL NOT LAST LONG AT ANY ONE
LOCATION...BUT COVERAGE WILL CONTINUE TO INCREASE THRU ROUGHLY 6
PM.
MLCAPE WILL ONLY PEAK AT 500-750 J/KG. DEEP LAYER SHEAR WILL BE
LESS THAN 15 KTS. SO SHWRS/TSTMS WILL BE PULSE-TYPE. THE ONLY REAL
ORGANIZATION WILL BE SMALL CLUSTERS WHERE SHWRS/TSTMS IN CLOSE
PROXIMITY GENERATE AND CONTRIBUTE TO A COMMON COLD POOL.
INSTABILITY AND SHEAR ARE TOO WEAK FOR STRONG STORMS. SO THAT
POTENTIAL THREAT WAS WITHDRAWN FROM THE HWO AT 1153 AM.
QPF: UNFORTUNATELY...THE SHWRS/TSTMS WONT LAST LONG ENOUGH TO BE
OF MUCH BENEFIT.
TONIGHT: THE SCT SHWRS/TSTMS ARE DIURNALLY DRIVEN. SO EXPECT MOST
OF THE ACTIVITY TO DIMINISH OR END 7PM-9PM. WITH THE NEXT COOL
FRONT MOVING IN LATE...CANT COMPLETELY RULE OUT SOME ISOLATED
RENEWED SHWR ACTIVITY /POSSIBLY THUNDER?/ S AND E OF THE TRI-
CITIES.
CLOUD DEBRIS FROM DISSIPATED SHWRS/TSTMS WILL EVENTUALLY BE
SCOURED FROM NW-SE...MAINLY N AND W OF THE TRI-CITIES. USED BIAS
CORRECTED CONSENSUS OF ALL GUIDANCE FOR LOW TEMPS.
TOMORROW: THE DAY WILL START WITH LEFTOVER CLOUDS FROM THE TRI-
CITIES S AND E. THESE CLOUDS WILL CONTINUE DEPARTING TO THE SE.
COULD STILL SEE A COUPLE SHWRS OVER THE FAR SE FRINGE OF THE FCST
AREA /E OF A LINE FROM YORK-NELSON-BELOIT/.
WIND: THE PRES GRADIENT WILL BE TIGHT BEHIND THE FRONT...WITH A
DECREASING 6 HR PRES RISE MAXIMUM. COMBINED WITH AN UNSTABLE BURST
OF COLD AIR ADVECTION...EXPECT ABOUT A 6-HR PERIOD OF WINDY
CONDITIONS FORENOON. WINDS WILL THEN DIMINISH IN THE AFTERNOON.
THE CONSENSUS OF ALL GUIDANCE /MOS AND RAW MODEL 2M TEMPS/
APPEARED TO HAVE A GOOD HANDLE ON DEWPOINTS. KNOCKED 1-2F OFF
AFTER EXAMINING FCST SOUNDINGS. BUT THIS WILL STILL KEEP MINIMUM
RH LEVELS JUST ABOVE 20%. THERE SHOULD ONLY BE ABOUT 3 HRS OF NEAR
CRITICAL FIRE DANGER...AS WINDS WILL BE SUBSIDING AS RH LEVELS
BOTTOM OUT.
THERE IS A FAIR AMOUNT OF SPREAD IN HIGH TEMP GUIDANCE. USED THE
WEIGHTED CONSENSUS OF THE RECENTLY BEST-PERFORMING GUIDANCE.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 324 PM CDT SUN APR 20 2014
WE BEGIN MONDAY NIGHT WITH BROAD RIDGING BUILDING IN ALOFT AND A
SPLIT FLOW REGIME. AT THE SURFACE...A RIDGE WILL APPROACH AS WELL.
THIS ENSURES A DRY FORECAST FOR MONDAY NIGHT INTO TUESDAY. ONE
THING OF NOTE FOR TUESDAY IS A SURFACE TROUGH STRENGTHENING IN THE
LEE SIDE OF THE ROCKY MOUNTAINS. MODELS VARY WITH THE PROGRESSION
OF THE SURFACE RIDGE IS FOR TUESDAY. THIS WILL SIGNIFICANTLY
INFLUENCE HOW WINDY WE WILL BE. THE ECMWF SOLUTION PLACES THE
RIDGE OVER THE MISSISSIPPI VALLEY BY 00Z WEDNESDAY AND OTHER
MODELS...INCLUDING THE GFS...HAVE COME IN LINE WITH THIS SOLUTION.
THERE WILL BE A CONSIDERABLE SOUTH BREEZE AS A RESULT. THIS WILL
INCREASE THE DEWPOINTS AT THE SURFACE AND PRIME US FOR INCREASED
INSTABILITY FOR WEDNESDAY. LOW TEMPERATURES SHOULD BE CONSIDERABLY
ABOVE NORMAL DUE TO THE WARM AIR ADVECTION TUESDAY NIGHT...AND
GOING TOWARD THE CONSRAW SOLUTION FOR LOWS BECAUSE OF THIS.
THERE IS INCREASING AGREEMENT AMONG NUMERICAL MODEL SOLUTIONS
HEADING INTO WEDNESDAY. WE WILL BE SQUARELY IN THE RELATIVELY
NARROW WARM SECTOR. BY AFTERNOON A DRY LINE WILL PROBABLY SCRAPE
THE SOUTHERN PART OF THE CWA. WITH INCREASING MOISTURE AND PLENTY
OF BULK SHEAR...THERE IS A GOOD SHOT AT SOME SEVERE
WEATHER...ESPECIALLY IN OUR SOUTH...AND LESS SO IN OUR NORTHERN
CWA. THE THREAT OF SEVERE WEATHER COULD CONTINUE WELL INTO THE
EVENING...BUT MOST SOLUTIONS HAVE THE COLD FRONT MOVING THROUGH
THE CWA BY MIDNIGHT OR SO. WE COULD HAVE SOME LINGERING SHOWERS IN
THE OVERNIGHT INTO THURSDAY.
THE NEXT FOCUS OF PRECIPITATION CHANCES ARRIVE FOR NEXT WEEKEND
AS A NEGATIVELY TILTED WAVE MOVES INTO THE PLAINS. ALTHOUGH THERE
ARE MODEL DIFFERENCES IN STRENGTH AND TIMING...THERE IS A GENERAL
INDICATION OF A CHANCE OF SHOWERS AND THUNDERSTORMS AT SOME POINT
OVER THE WEEKEND. IT IS STILL VERY MUCH UP IN THE AIR ON WHETHER
WE COULD GET SEVERE WEATHER OUT OF THIS. NOT ENOUGH SEVERE
PARAMETERS HAVE COME TOGETHER FOR ME TO MENTION THE POSSIBILITY OF
STRONG OR SEVERE THUNDERSTORMS IN THE HWO.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1217 AM CDT MON APR 21 2014
VFR CONDITIONS ARE FORECAST FOR THE GRAND ISLAND AIRPORT BUT
THERE AREA A WEATHER CHANGES. THE MAIN CHANGES WILL OCCUR WITH
AN ADVANCING FRONTAL BOUNDARY SLATED TO PASS BY AROUND JUST PRIOR
TO SUNRISE. AHEAD OF AND ALONG THE FRONT...SOME ISOLATED SHOWERS
MAY BE IN THE AREA BUT NOT CONFIDENT ENOUGH TO SAY FOR SURE THE
AIRPORT WILL ACTUALLY MEASURE ANY RAINFALL. HAVE INCLUDING THE
SHOWERS IN THE VICINITY. ONCE THE FRONT GOES THROUGH...NORTH
WINDS WILL PICK UP DRAMATICALLY AND GUST OVER 25KTS BY LATE
MORNING AND DURING THE AFTERNOON. MID LEVEL CEILINGS WILL GIVE
WAY TO SOME SCATTERED HIGH CLOUDS BY LATE MORNING.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE...NOAA/NWS/MORITZ
SHORT TERM...HALBLAUB
LONG TERM...HEINLEIN
AVIATION...NOAA/NWS/MORITZ
AREA FORECAST DISCUSSION
NWS BISMARCK ND
348 AM CDT MON APR 21 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 348 AM CDT MON APR 21 2014
NO MAJOR FORECAST HIGHLIGHTS IN THE SHORT TERM PERIOD.
CURRENTLY...QUASI-ZONAL FLOW ACROSS THE NORTHERN PLAINS WITH A
STRONG EMBEDDED S/WV TROUGH PUSHING EAST ALONG THE INTERNATIONAL
BORDER...NOW CENTERED NEAR TO EAST OF LAKE WINNIPEG. WRAP AROUND
MOISTURE IN THE FORM OF LOW LEVEL STRATUS SURGING SOUTH AND EAST
ACROSS MY NORTHERN COUNTIES THE PAST COUPLE OF HOURS. AT THIS TIME
DO NOT ANTICIPATE ANY PRECIPITATION ASSOCIATED WITH THE STRATUS.
WILL CONTINUE TO MONITOR.
LOW BKN-OVC CLOUDS WILL CONTINUE TO MOVE ACROSS NORTHWEST AND
NORTH CENTRAL NORTH DAKOTA NOW THROUGH 10Z...EVENTUALLY DEPICTED
BY BOTH THE RAP AND 00Z/06Z NAM TO PUSH AS FAR SOUTH AS BISMARCK
AND JAMESTOWN 10-14Z. AFTERWARDS...STRATUS SHOULD DISSIPATE/BURN
OFF BY THE EARLY AFTERNOON. THE MORNING CLOUDS COUPLED WITH CAA
THE PAST SEVERAL HOURS WILL RESULT IN HIGH TEMPERATURES TODAY IN
THE 50S ALONG TO NORTH AND EAST OF THE MISSOURI RIVER...60S SOUTH
AND WEST OF THE MISSOURI.
RETURN FLOW/WAA TONIGHT AS AN UPPER LEVEL RIDGE OF HIGH PRESSURE
AMPLIFIES ACROSS THE ROCKIES TODAY THEN PROPAGATES EAST INTO THE
HIGH PLAINS TONIGHT.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 348 AM CDT MON APR 21 2014
ACTIVE PERIOD EXPECTED WITH STRONG STORM SYSTEM APPROACHING THE
REGION TUESDAY NIGHT. LARGE SURFACE LOW INITIALLY CENTERED OVER
CENTRAL MONTANA 00Z WEDNESDAY TRANSITIONS TO DUAL SURFACE LOWS
OVER SOUTHEASTERN SASKATCHEWAN AND SOUTHEAST MONTANA BY 12Z WED AS
SHORTWAVE/90KT H250 JET STREAK ROTATE AROUND PARENT UPPER LOW.
BREEZY TO WINDY EAST/SOUTHEAST WINDS WILL OCCUR ALSO WITH TIGHT
SURFACE GRADIENT AND 850MB WINDS TO 45KTS LATE TUESDAY AND TUESDAY
NIGHT. SPC CONTINUES TO INCLUDE THE WESTERN HALF OF THE STATE IN
GENERAL THUNDERSTORM AREA WITH MODELS INDICATING LOW CAPE NUDGING
INTO THIS REGION ALONG WITH H7-H5 LAPSE RATES APPROACHING 8C/KM
TUESDAY NIGHT AHEAD OF THE COLD FRONT. MODELS CONTINUE TO SHOW
HIGHEST QPF ACROSS NORTH AND EAST AS DRY SLOT IS MORE OF A FACTOR
ACROSS WESTERN AND SOUTHERN AREAS. WEDNESDAY NIGHT INTO THURSDAY
THE CLOSED UPPER LOW AND ASSOCIATED SURFACE LOW MOVE ACROSS THE
NORTHERN PLAINS. MODEL DIFFERENCES INCREASE WITH THIS FEATURE WITH
THE GFS A LITTLE FASTER AND FARTHER SOUTH COMPARED TO ECMWF. BOTH
MODELS...HOWEVER...BRING SUB 0C H850 AIR ACROSS THE STATE IN
NORTHERLY FLOW BEHIND THE SYSTEM THURSDAY NIGHT WITH LIGHT PRECIP
IN THE FORM OF RAIN CHANGING TO SNOW FROM NORTH TO SOUTH.
SUBSTANTIAL MODEL DIFFERENCES BY NEXT WEEKEND WITH GFS SHOWING
STRONGER RIDGE AND DRYER WEATHER OVER ND ON SATURDAY WHILE ECMWF
HAS LESS AMPLIFIED PATTERN AND ANOTHER BATCH OF PRECIP MOVING IN
UNDER SOUTHWEST FLOW ALOFT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 348 AM CDT MON APR 21 2014
MVFR STRATUS SURGING SOUTH ACROSS NORTHERN NORTH DAKOTA AT THIS
TIME...AND WILL CONTINUE TO DEVELOP SOUTH AND EAST THROUGH MID-
MORNING. IMPACTED LOCATIONS INCLUDE KISN-KMOT-KJMS AND POSSIBLY
KBIS. OTHERWISE VFR AT ALL TAF SITES THE REST OF THE 06Z FORECAST
PERIOD.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...NH
LONG TERM...JNS
AVIATION...NH
AREA FORECAST DISCUSSION
NWS BISMARCK ND
110 AM CDT MON APR 21 2014
.UPDATE...
ISSUED AT 110 AM CDT MON APR 21 2014
FORECAST REMAINS MAINLY ON TRACK. MAIN UPDATE WAS TO INCREASE SKY
COVER NORTH AS AN AREA OF LOW STRATUS PUSHES SOUTH FROM CANADA.
THE LATEST RAP AND 00Z NAM ARE CAPTURING THESE CLOUDS VERY WELL SO
LEANED HEAVILY ON THEIR FUTURE DEPICTION. STRATUS LOOKS TO LINGER
THROUGH MID MORNING THEN SHOULD BURN OFF BY 17-18Z.
UPDATE ISSUED AT 940 PM CDT SUN APR 20 2014
LOCAL RADARS SHOW THE NARROW BAND OF SHOWERS ASSOCIATED WITH THE
COLD FRONT ARE JUST ABOUT OUT OF THE REGION. ANOTHER ONE OR TWO
HOURS OF WIDELY SCATTERED SHOWERS IN THE NORTHERN JAMS RIVER
VALLEY IS ABOUT IT. UPPER LOW CIRCULATION IN CANADA WITH H850
COLD ADVECTION SHOULD BRING IN SOME CLOUDS NORTH CENTRAL LATE
TONIGHT. OTHERWISE MOSTLY CLEAR. LOWERED THE MIN TEMPS 2 TO 4
DEGREES CENTRAL AND EAST AS LOW RH/DRY AIR AND RAPIDLY
DIMINISHING WINDS SHOULD ALLOW TEMPS TO FALL A BIT MORE TONIGHT.
UPDATE ISSUED AT 624 PM CDT SUN APR 20 2014
AS OF 620 PM CDT...THE COLD FRONT HAS MOVE TO A RUGBY TO HARVEY TO
LINTON LINE AND MOVING RAPIDLY EAST. ONLY SOME LIGHT SHOWERS NORTH
BUT THE SHOWERS ARE ENHANCING THE WINDS A BIT NORTH CENTRAL DO TO
EVAPORATIVE COOLING. WEST OF THE FRONT A WELL MIXED LAYER HAS
RESULTED IN GUSTY NORTHWEST WINDS OF 25 TO 35 MPH. THESE ARE
EXPECTED TO DIMINISH RAPIDLY AFTER SUNSET. ADJUSTED WINDS AND
CLOUDS TO FOLLOW THE FRONT WITH THIS FORECAST
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 323 PM CDT SUN APR 20 2014
A COLD FRONT HAS ENTERED WESTERN NORTH DAKOTA THIS AFTERNOON.
AHEAD OF THE FRONT...TEMPERATURES HAVE WARMED INTO THE 70S OVER
CENTRAL NORTH DAKOTA...AND INTO THE UPPER 60S OVER NORTH CENTRAL
NORTH DAKOTA. NO PRECIPITATION HAS DEVELOPED ALONG THE BOUNDARY
JUST YET. HOWEVER...WILL MAINTAIN SLIGHT CHANCES FOR SHOWERS
PRIMARILY OVER NORTHERN NORTH DAKOTA THROUGH THE LATE
AFTERNOON/EARLY EVENING AS THE MAIN UPPER SHORTWAVE TRAVERSES THE
INTERNATIONAL BOUNDARY. THE COMBINATION OF WARM TEMPERATURES AND
BREEZY CONDITIONS WILL CONTINUE TO GENERATE A "VERY HIGH" FIRE
DANGER OVER MOST OF WESTERN AND CENTRAL NORTH DAKOTA THIS
AFTERNOON.
DRY CONDITIONS ARE EXPECTED AREAWIDE OVERNIGHT. BOUNDARY LAYER WINDS
AROUND 30 KNOTS SHOULD KEEP TEMPERATURES ABOVE NORMAL TONIGHT...WITH
LOWS FORECAST TO RANGE FROM THE UPPER 30S TO LOW 40S.
A DRY DAY IS FORECAST FOR MONDAY AS HIGH PRESSURE BUILDS INTO THE
REGION. HOWEVER...COOLER CANADIAN AIR IS EXPECTED TO ROTATE SOUTH
BEHIND THE DEPARTING UPPER SHORTWAVE ACROSS WESTERN AND CENTRAL
NORTH DAKOTA MONDAY. TEMPERATURES SHOULD BE ABOUT A CATEGORY
ABOVE NORMAL...WITH HIGHS RANGING FROM THE UPPER 50S TO LOW 60S.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 323 PM CDT SUN APR 20 2014
THE HIGHLIGHTS OF THE EXTENDED FORECAST ARE A POTENTIAL STORM
SYSTEM FOR TUESDAY NIGHT INTO THURSDAY...FOLLOWED BY BELOW NORMAL
TEMPERATURES.
THE 12 UTC GUIDANCE SUITE CONTINUES TO SUGGEST SHOWERS AND
THUNDERSTORMS DEVELOPING ACROSS WESTERN AND CENTRAL NORTH DAKOTA
TUESDAY NIGHT INTO WEDNESDAY MORNING ALONG AND AHEAD OF AN
OCCLUDING WARM FRONT SUPPORTED BY A STRONG LOW LEVEL JET AND STEEP
MID LEVEL LAPSE RATES. THE THREAT FOR SHOWERS AND THUNDERSTORMS
DURING THE DAY ON WEDNESDAY IS FORECAST TO BE FOCUSED ACROSS THE
NORTH THROUGH THE JAMES RIVER VALLEY AS A DRY SLOT BEGINS TO
OVERTAKE THE WEST. THE 12 UTC SUITE...COMPARED TO
YESTERDAY...SUGGESTS THIS DRY SLOT WILL OVERTAKE MUCH OF WESTERN
AND CENTRAL NORTH DAKOTA WEDNESDAY NIGHT INTO THURSDAY...RESULTING
IN SIGNIFICANTLY LESS QPF. PRECIPITATION CHANCES INCREASE ONCE
AGAIN DURING THE SECOND HALF OF THURSDAY AS A STRONG COLD FRONT IS
FORECAST TO PROPAGATE SOUTH OUT OF CANADA. THEREAFTER...WELL BELOW
NORMAL HIGHS IN THE 40S ARE FORECAST FRIDAY INTO NEXT WEEKEND AS A
COLD...STRONG SURFACE HIGH BUILDS INTO THE NORTHERN PLAINS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 110 AM CDT MON APR 21 2014
A TROUGH OF LOW PRESSURE ACROSS SOUTHERN CANADA IS FORECAST TO
MOVE SOUTH INTO NORTH DAKOTA MONDAY MORNING. THIS WILL BRING SOME
STRATO-CUMULUS CLOUDS INTO THE NORTHWEST AND NORTH CENTRAL BETWEEN
NOW AND 12Z. SCT-BKN CLOUDS 1-3 THOUSAND FOOT AGL EXPECTED FOR
THE MORNING HOURS KISN-KMOT...POSSIBLY KJMS. OTHERWISE VFR AT ALL
TAF SITES.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...NH
SHORT TERM...TM
LONG TERM...AYD
AVIATION...NH/WAA
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
128 AM EDT MON APR 21 2014
.SYNOPSIS...
HIGH PRESSURE WILL REMAIN ACROSS THE AREA BEFORE A COLD FRONT
CROSSES EAST ON TUESDAY. DRY HIGH PRESSURE BUILDS BACK IN WEDNESDAY
AND THURSDAY WITH ANOTHER COLD FRONT AFFECTING THE REGION ON FRIDAY.
&&
.NEAR TERM /THROUGH TODAY/...
AS OF 130 AM...A QUIET NEAR TERM IS EXPECTED...AS SHARP UPR RIDGE
AXIS TRANLATES EAST ACRS THE CWFA. AN INVERTED SFC RIDGE AXIS ALSO
REMAINS INVOF THE REGION...RESULTING IN LGT NE FLOW EAST OF THE MTNS
AND DRY CONDITIONS. THERE MAY BE SOME PATCHY FROST IN THE NORTHERN
MTNS...BUT NOTHING WIDESPREAD ACRS THE REST OF THE HIGH TERRAIN TO
WARRANT A FROST ADVISORY. TEMPS CURRENTLY LOOK ON TRACK.
AS OF 1030 PM...NC PIEDMONT STRATOCU HAS BEEN STEADILY OOZING AWAY
FROM THE FORECAST AREA THIS EVENING...SO THE SKY COVER FORECAST HAS
BEEN LOWERED ACROSS OUR SOUTHEAST TIER OF ZONES. OTHERWISE...
PRIMARILY THIN CIRRUS WILL PASS OVER THE REGION THROUGH THE
OVERNIGHT...BUT THIS IS NOT EXPECTED TO HAVE A MAJOR IMPACT ON THE
NOCTURNAL COOLING CYCLE. WITH LIGHT MIXING EXPECTED IN THE PIEDMONT
TONIGHT...MIN TEMPS ARE EXPECTED TO AVERAGE JUST A LITTLE BELOW
NORMAL...WHILE SHELTERED MTN VALLEYS WILL AVERAGE AT LEAST 5 DEGREES
BELOW CLIMO. IN FACT...IT APPEARS PATCHY FROST IS LIKELY IN
SHELTERED AREAS OF THE SRN/CTRL MTNS MONDAY MORNING...AND WE HAVE
ADDED THIS TO THE FORECAST. IN ADDITION...VALLEY FOG LOOKS LIKE A
DECENT BET...PRIMARILY IN THE LITTLE TENN BASIN AND ADJACENT
DRAINAGES.
AS OF 750 PM SUNDAY...OTHER THAN PATCHY STRATOCU ACROSS THE EXTREME
SE TIER OF ZONES...SKIES ARE CLEAR ACROSS THE AREA AT MID-EVENING.
MODEL SOLUTIONS ARE QUITE DISPARATE REGARDING THE EVOLUTION OF THIS
STRATOCU LAYER OVERNIGHT...WITH THE NAM BEING SOMEWHAT OF AN OUTLIER
IN DRAGGING IT WEST TO ENCOMPASS MUCH OF THE NC PIEDMONT/EASTERN SC
PIEDMONT LATER THIS EVENING. IN LIGHT OF THIS...HAVE OPTED TO
INTRODUCE SKY COVER AT THE MOSTLY CLEAR/PARTLY CLOUDY END OF THE
SPECTRUM ACROSS THE EASTERN THIRD OF THE AREA.
AS OF 150 PM EDT SUNDAY...WITH THE UPPER LOW SLOWLY MOVING OUT TO
SEA...ONLY THE FAR EASTERN ZONES SHOULD SEE ANY CLOUD COVER THIS
EVENING. THE NAM IS QUITE AGGRESSIVE IN BRINGING CLOUDS INTO THE WRN
NC PIEDMONT...BUT AS THE GFS AND RUC DO NOT DO THIS...I/VE GONE WITH
A SKY FORECAST CLOSER TO THE DRIER MODELS. THERE SHOULD BE MORE
LOCALLY DENSE FOG IN THE SOUTHWEST IN MTN VALLEYS OVERNIGHT. DRY AIR
AND WEAK MIXING SHOULD KEEP MOST OTHER LOCATIONS ACROSS THE FA FROM
SEEING ANY FOG OVERNIGHT. MIN TEMPS WILL BE COOL...BUT THEY SHOULD
BE WARM ENOUGH TO PREVENT FROST OVER ALL BUT SOME OF THE INTERIOR
NORTHERN MOUNTAIN VALLEYS. MONDAY WILL BE SEASONABLY MILD WITH
INCREASING HIGH CLOUDS DURING THE AFTERNOON HOURS.
&&
.SHORT TERM /TONIGHT THROUGH WEDNESDAY/...
AS OF MIDDAY SUNDAY...UPPER PATTERN BEGINS TO AMPLIFY ACRS THE ERN
CONUS MON NIGHT AS DEEP RIDGE PUSHES INTO THE GREAT PLAINS. CORE OF
TROUGH BEGINS TO DIG ACRS THE GREAT LAKES...AND SFC LOW SUBSEQUENTLY
DEVELOPS AND MOVES INTO NEW ENGLAND DURING THE DAY TUE. THE TRAILING
COLD FRONT IS STILL PROGGED TO ENTER OUR CWFA AT THAT TIME...MOVING
OUT TUE EVENING. WE WILL BE WELL SOUTH OF THE BETTER FORCING THOUGH
SOME DPVA IS PROGGED AS THE AXIS OF THE BROAD TROUGH PASSES.
FRONTOGENESIS AND LLVL CONVERGENCE FIELDS ARE MURKY...SO PRECIP
CHANCES MOSTLY RESULT FROM DECENT PREFRONTAL INSTABILITY. CAPE
PROFILES ARE SKINNY ON PROG SOUNDINGS AND DEEP SATURATION IS
INITIALLY EVIDENT. SHEAR PARAMETERS CONTINUE TO PROMPT LITTLE
CONCERN...BUT IN THE WAKE OF THE UPPER TROUGH DRYING RAPIDLY OCCURS
ABV 700 MB. THIS OCCURS IN THE MID TO LATE AFTN WHEN SOME SFC BASED
INSTABILITY IS STILL PRESENT. THUS SOME OF THE LATER STORM ACTIVITY
COULD POSE A MICROBURST AND DAMAGING WIND THREAT...MAINLY OVER THE
PIEDMONT. TEMPS MON NIGHT AND TUE WILL BE A CATEGORY OR TWO ABOVE
NORMAL.
DEEP LAYER DRYING CONTINUES TUE NIGHT AS PLAINS RIDGE MOVES INTO THE
ERN US...AND SKIES WILL CLEAR OVERNIGHT...PERHAPS MORE SLOWLY IN THE
MTNS WHERE A VERY SHALLOW SFC BASED MOIST LAYER REMAINS IN NW FLOW.
BRISK WINDS ARE LIKELY IN THE HIGH ELEVATIONS AT THAT TIME BUT THESE
SUBSIDE TOWARD DAWN WED. DRY AND MOSTLY CLEAR CONDITIONS PERSIST THRU
WED WITH SUBSIDENCE INVERSION ACRS THE FA BUT LACKING MOISTURE
ANYWAY. THICKNESSES DO DROP A BIT FOR WED...RETURNING TEMPS TO AROUND
NORMAL DESPITE PRIME INSOLATION.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
AS OF 230 PM EDT SUNDAY...THE EXTENDED RANGE PERIOD INITIALIZES ON
WEDNESDAY EVENING AS DEEP LAYER RIDGING PREVAILS ACROSS THE
SOUTHEAST. A SURFACE HIGH DIVING OUT OF ONTARIO WILL QUICKLY
TRANSITION TO A BERMUDA TYPE HIGH BY THURSDAY AFTERNOON SETTING UP
RETURN FLOW. MEANWHILE...A NORTHERN STREAM LOW AMPLITUDE UPPER TROF
WILL PUSH THROUGH THE NORTHERN PLAINS WITH SURFACE CYCLOGENESIS
OCCURRING OVER THE CENTRAL PLAINS. A COLD FRONT WILL PUSH
THROUGH THE MISSISSIPPI RIVER VALLEY ON THURSDAY EVENING AS THE
PARENT SURFACE CYCLONE EJECTS NORTHEAST INTO THE GREAT LAKES REGION.
ABOVE MENTIONED HIGH PRESSURE WILL PREVAIL ACROSS THE SOUTHERN
APPALACHIANS...AHEAD OF THE APPROACHING FRONT ON FRIDAY
MORNING/AFTERNOON. A WARM FRONT WILL SURGE NORTHWARD FROM THE GULF
AND WESTERN ATLANTIC SOURCE REGIONS ALLOWING FOR INCREASING
DEWPOINTS AND STEEPENING LAPSE RATES DURING THE AFTERNOON HOURS.
THIS WILL LEAD TO MODEST INSTABILITY ACROSS THE CWFA WITH GFS/ECMWF
SOLUTIONS INDICATIVE OF SBCAPE IN EXCESS OF 1000J/KG WITH ENOUGH
SHEAR TO SUPPORT SOME ORGANIZED CONVECTION. STILL TOO MUCH
UNCERTAINTY TO DIAL IN ON STORM MODES AND SPECIFIC TIMING/INTENSITY.
HOWEVER...CURRENT FCST SOUNDINGS DO INDICATE PW VALUES APPROACHING
1.5 INCHES LEADING TO MODERATELY HEAVY RAIN RATES WITH CAPE PROFILES
SUPPORTIVE OF LARGE HAIL. DUE TO UNCERTAINTY...CAPPED POPS AT HIGH
END CHANCE LEVELS ACROSS THE REGION FOR FRIDAY. THE FRONT WILL PASS
INTO THE COASTAL PLAINS/MIDLANDS BY EARLY MORNING SATURDAY LEADING
TO A DRY FCST UNTIL SUNDAY AFTERNOON. AT THAT TIME POPS SLOWLY RAMP
UP ACROSS THE WESTERNMOST ZONES AS ANOTHER SYSTEM MOVES THROUGH THE
MIDSOUTH AND INTO THE TENNESSEE VALLEY. TEMPERATURES THROUGH THE
EXTENDED RANGE PERIOD WILL REMAIN AT OR JUST ABOVE NORMAL LEVELS
DESPITE THE FROPA FRIDAY EVENING.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
AT KCLT...A QUIET TAF PERIOD AS SFC HIGH PRES AXIS TRANSLATES ACRS
THE AREA...WITH GENERALLY SKC OR FEW/SCT250 THRU THE PERIOD. LGT
WINDS WILL FAVOR A NE DIRECTION UNTIL ABOUT NOON...THEN BECOME
VARIABLE DURING THE AFTN BEFORE SWITCHING TO SW.
ELSEWHERE...SIMILAR TO KCLT ABOVE...WITH LGT NE WINDS OR VARIABLE
THRU MID MORNING...THEN FAVORING SW BY EARLY AFTN. FCST SNDGS SHOW
POSSIBLE SOME HIGH-BASED CUMULUS DEVELOPING ACRS THE NC MTNS AND
INTO THE UPSTATE LATE AFTN/EARLY EVENING...BUT OTHERWISE CIRRUS ONLY
CLOUDS EXPECTED THRU THE PERIOD.
OUTLOOK...A FAIRLY WET FRONTAL SYSTEM...WITH PIEDMONT
THUNDERSTORMS...IS EXPECTED ON TUE...WITH DRYING RETURNING MID WEEK.
CONFIDENCE TABLE...
05-11Z 11-17Z 17-23Z 23-05Z
KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAVL HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100%
KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...SBK
NEAR TERM...ARK/JDL/MCAVOY
SHORT TERM...WIMBERLEY
LONG TERM...CDG
AVIATION...ARK
AREA FORECAST DISCUSSION...UPDATED
NWS ABERDEEN SD
1227 AM CDT MON APR 21 2014
.UPDATE...
SEE UPDATED AVIATION DISCUSSION BELOW.
CURRENT RADAR SHOWS AN AREA OF TSTORMS MOVING THROUGH LYMAN AND
SOUTHERN HUGHES COUNTY. LIKE THE HRRR DEPICTION OF CONVECTIVE
PROGRESSION EASTWARD SO NUDGED POPS A BIT TO REFLECT THE 21Z
GUIDANCE. EVEN THOUGH RADAR IS ALSO SHOWING SOME WEAK RETURNS
ACROSS THE EASTERN CWA KEPT THIS AREA DRY. DUE TO THE 35 DEGREE
DEWPOINT SPREAD AND THE LACK OF ANY STRONG ECHOES THIS ACTIVITY IS
LIKELY ALL VIRGA IN THE EAST FOR NOW.
DROPPED OVERNIGHT LOWS ABOUT FIVE DEGREES IN THE NORTH...FROM THE
JAMES VALLEY TO CORSON COUNTY. EVEN WITH MOISTER AID ADVECTING IN
FROM THE WEST ACROSS THE SOUTH...NORTHERN UPSTREAM OBS HAVE
DEWPOINTS IN THE 20S TO LOWER 30S WHICH SHOULD ALLOW TEMPERATURES
TO TANK AFTER SUNSET SINCE WINDS ARE LIGHT.
&&
.PREVIOUS DISCUSSION...
.SHORT TERM...TONIGHT THROUGH TUESDAY NIGHT
A WEAK LOW PRESSURE SYSTEM AND ASSOCIATED COOL FRONT WILL TRACK
ACROSS THE AREA TONIGHT. FAIRLY WARM TEMPERATURES HAVE AIDED IN A
LITTLE INSTABILITY DEVELOPMENT ACROSS THE SOUTHERN PORTION OF THE
STATE...AND MAY SEE SOME SHOWER AND THUNDERSTORM DEVELOPMENT THIS
EVENING OVER THE SOUTHERN CWA. MOISTURE IS PRETTY LIMITED...SO NOT
ANTICIPATING ANY SEVERE WEATHER. HIGH PRESSURE MOVES IN BEHIND THE
EXITING LOW ON MONDAY. EVEN THOUGH TEMPERATURES WILL BE A BIT
COOLER...DECENT MIXING WILL BRING BREEZY TO WINDY CONDITIONS TO
THE EASTERN CWA...AND WITH THE DRIER AIR IN PLACE...THE POTENTIAL
IS THERE FOR FIRE WEATHER ISSUES. THEREFORE...HAVE ISSUED A FIRE
WEATHER WATCH FOR THE EASTERN CWA...INCLUDING THE TWO MINNESOTA
COUNTIES FOR MONDAY AFTERNOON. AFTER THAT...THINGS STAY QUIET
UNTIL TUESDAY NIGHT WHEN WARM FRONTAL RAIN SHOWERS LOOK TO AFFECT
MUCH OF THE CWA AHEAD OF ANOTHER APPROACHING LOW...ALONG WITH
GUSTY WINDS SPREADING FROM WEST TO EAST.
WITH THE HIGH DOMINANT ON MONDAY...SLIGHTLY COOLER TEMPS IN THE
60S WILL BE COMMON FOR HIGHS...WITH JUST A BIT OF A RISE IN HIGHS
ON TUESDAY...MAINLY MID 60S TO LOWER 70S. OVERNIGHT LOWS WILL BE
MAINLY IN THE 40S TONIGHT AND TUESDAY NIGHT...WITH COOLER 30S
EXPECTED MONDAY NIGHT.
.LONG TERM...WEDNESDAY THROUGH SUNDAY
THE MEDIUM RANGE MODELS CONTINUE TO SHOW A PROGRESSIVE PATTERN
THROUGH THE EXTENDED PERIOD. TIMING OF PRECIP WILL BE TRICKY AS
DETAILS DIFFER ALONG WITH THE PRESENCE OF A DRY SLOT WEDNESDAY AND
THURSDAY AS THE UPPER LOW PUSHES INTO NE MT. HAVE TRENDED
THUNDERSTORM CHANCES HIGHEST IN THE EAST WHERE DRY SLOT INFLUENCE
APPEARS TO BE NOT AS STRONG. MODELS DIFFER ON WHAT THIS UPPER WILL
DO...EC HAS IT WEAKENING THEN REORGANIZING IT OVER NORTHERN MN.
EXPECT SHOWERS ON BACKSIDE OF LOW FRIDAY. CONFIDENCE LOW ON
POSITION OF DRY SLOT AT THIS TIME BUT WILL HAVE TO BE WATCHED AS
IT WILL PLAY A BIG ROLE ON WHAT AREAS STAY ON THE DRIER SIDE.
THE UPPER RIDGE LOOKS TO POP BACK INTO THE AREA SATURDAY WITH
SHOWERS AND THUNDERSTORMS DEVELOPING AGAIN SATURDAY
AFTERNOON/NIGHT AS FLOW QUICKLY BECOMES SOUTHWEST ALOFT. TEMPS
WILL HAVE A HARD TIME REBOUNDING IN THE RIDGE WITH COOLER AIR IN
PLACE AND A QUICK RETURN OF CLOUDS AND PRECIPITATION CHANCES.
&&
.AVIATION...
06Z TAFS FOR THE KABR...KATY...KPIR AND KMBG TERMINALS
VFR CONDITIONS WILL PREVAIL THROUGH THE TAF PERIOD. A WEAK FRONT
IS MOVING THROUGH THE REGION OVERNIGHT TURNING WINDS TO THE
NORTHWEST. THE FRONT HAS ALREADY PASSED THROUGH ALL SITES EXCEPT
KATY WHICH SHOULD EXPERIENCE VERY GUSTY WINDS WITH FROPA BRIEFLY
BETWEEN 6Z AND 8Z. NORTHWEST WINDS WILL BECOME GUSTY AT 15 TO 30
KTS AT ALL SITES BY LATE MORNING MONDAY.
&&
.ABR WATCHES/WARNINGS/ADVISORIES...
SD...FIRE WEATHER WATCH FROM THIS AFTERNOON THROUGH THIS EVENING FOR
PRAIRIE COTEAU-RED RIVER VALLEY-UPPER JAMES RIVER.
MN...FIRE WEATHER WATCH FROM THIS AFTERNOON THROUGH THIS EVENING FOR
BIG STONE-TRAVERSE.
&&
$$
UPDATE...WISE
SHORT TERM...PARKIN
LONG TERM...SCARLETT
AVIATION...TDK
WEATHER.GOV/ABERDEEN
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
1155 PM CDT SUN APR 20 2014
.UPDATE...
ISSUED AT 911 PM CDT SUN APR 20 2014
BAND OF SHOWERS AND THUNDERSTORMS ALONG FRONT AND LOW HAS BEEN
EXPANDING OVER THE WESTERN EDGE OF OUR FORECAST AREA. THIS IS IN
LINE WITH CURRENT PROJECTIONS BY THE HRRR AND EVEN THE RAP. LESS
CERTAIN IS HOW ACTIVITY WILL BEHAVE SOUTHEAST...IN NORTHWEST
IOWA...HAVING UNDERGONE A DECREASE LAST HOUR OR TWO...BUT EXPECT
SOME SEPARATE REGENERATION THERE AS THE LOW/FRONT APPROACH.
ANYWAY...THE MAIN CHANGE FOR NOW IS TO INCREASE POPS/COVERAGE OF
THE SHOWERS AND STORMS NORTH FROM THE EARLIER SLIGHT CHANCE.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 406 PM CDT SUN APR 20 2014
ELEVATED BAND OF SHOWERS AND ISOLATED THUNDERSTORMS DEVELOPING IN
NORTHEAST NEBRASKA THIS AFTERNOON AND GRADUALLY WORKING/DEVELOPING
NORTHEAST. NOT ANTICIPATING A WHOLE LOT OF ACTIVITY FROM THIS
CONVECTION BUT SHOULD PRODUCE SOME ISOLATED TO SCATTERED SHOWERS
WITH A FEW EMBEDDED THUNDERSTORMS. ANOTHER AREA LIKELY TO PRODUCE
ISOLATED ACTIVITY WILL BE IN CENTRAL SD NEAR AN INCOMING WEAK
CONVERGENT BOUNDARY. UPPER LEVEL SUPPORT NOT TOO GOOD AND DRY LOW
LEVELS SUGGEST THAT MAYBE NOTHING WILL GET GOING BUT STILL WORTH AN
ISOLATED THREAT AT THIS POINT.
THE MAIN AREA TO FOCUS ON WILL AGAIN BE NORTHWEST IOWA WHERE THERE
IS A BETTER COMBINATION OF UPPER LEVEL FORCING...INSTABILITY AND AND
LOW TO MID LEVEL FRONT. WILL KEEP LIKELIES GOING AND ALSO THE IDEA
THAT SEVERE THUNDERSTORMS WILL NOT BE A THREAT. CAPE VALUES MAY
APPROACH 500 TO 1000 J/KG THIS EVENING BUT WITH THE MODELS OVERDOING
THE LOW LEVEL MOISTURE THOSE VALUES COULD BE A BIT PESSIMISTIC. THE
BETTER CHANCES FOR PRECIPITATION SHOULD SHIFT SOUTHEAST OF THE AREA
LATE TONIGHT AS THE UPPER LEVEL WAVE TO THE NORTH BRINGS IN DRIER
AND MORE STABLE AIR. LOWS LIKELY TO RANGE FROM THE MID 40S IN THE
NORTHERN CWA TO THE MID 50S IN PARTS OF NORTHWEST IOWA.
THIS DRIER AND MORE STABLE AIR MASS WILL ALSO COME WITH A WELL MIXED
ATMOSPHERE AND DECENT PRESSURE GRADIENT WHICH WILL LEAD TO A WINDY
MONDAY IN MOST LOCATIONS. RECENT TRENDS IN GUIDANCE HAS BEEN TO
FORECAST DEW POINT TEMPERATURES TOO HIGH...ESPECIALLY IN A WELL
MIXED ENVIRONMENT SO WENT MUCH CLOSER TO THE BIAS CORRECTED OUTPUT
WHICH HAS BEEN HANDLING OUR DRY GROUND BETTER AS THE MODELS SEEM TO
BE HAVING TROUBLE WITH OUR DRIER THAN NORMAL BOUNDARY LAYER.
SO...BECAUSE OF THE LOW DEW POINTS AND HIGH WINDS WENT AHEAD AND
ISSUED A FIRE WEATHER WATCH FOR MOST OF THE AREA AS AFTERNOON
HUMIDITY VALUES LIKELY TO FALL BELOW 25 PERCENT IN MANY LOCATIONS AS
HIGHS CLIMB INTO THE UPPER 60S TO LOWER 70S.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 406 PM CDT SUN APR 20 2014
HIGH PRESSURE WILL CONTINUE TO EASE SOUTHWARD INTO THE REGION ON
MONDAY NIGHT. DIMINISHING WINDS AND MAINLY CLEAR SKIES...ALONG WITH
A DRIER AIRMASS SHOULD LEAD TO LOWS TOWARD THE LOWER END OF THE
FORECAST ENVELOPE...MAINLY MID TO UPPER 30S.
BY TUESDAY...UPPER LEVEL RIDGING WILL BUILD EASTWARD ACROSS THE AREA
ALONG WITH AN EASTWARD RETURN OF A FAIRLY STRONG MID LEVEL FRONTAL
ZONE. MOISTURE IS PRETTY ANEMIC THROUGH THE DAY AT LOWER LEVELS...
BUT ELEVATED PARCELS AROUND 700 HPA OR A BIT HIGHER DO INDICATE
SOME CONVECTIVE INSTABILITY. HAVE NOT INCLUDED ANY PRECIPITATION
WORKING SLOWLY EASTWARD ACROSS THE CWA...BUT WOULD CERTAINLY THINK
AT LEAST A COUPLE OF SPRINKLES WOULD ACCOMPANY THE THICKENING MID
CLOUDS THROUGH THE DAY TOWARD AT LEAST I29 BY LATE DAY. SHADED
DEWPOINT FORECAST TOWARD DRIER RAW PROFILES...AS HAS BEEN THE CASE
OF LATE.
STRONG LOW LEVEL JET OF 50 TO 60 KNOTS DEVELOPS ON TUESDAY NIGHT
WITH MOISTURE SURGE WORKING RAPIDLY NORTHWARD FROM THE SOUTHERN
HIGH PLAINS. FAIRLY GOOD WAVE MOVING THROUGH RIDGE DURING THE
NIGHT...MAIN CONVERGENCE WITH LOW LEVEL JET ESTABLISHES
NORTH...BUT CONTINUED MID LEVEL INSTABILITY WITH 8-9C/KM AND
INCREASING MOISTURE SUGGESTS A BETTER COVERAGE OF SHOWERS AND
ISOLATED THUNDER WITH TIME OVERNIGHT. WINDS WILL ALSO BECOME AN
ISSUE LATER IN THE NIGHT...AND COULD GET SOMEWHAT CLOSE TO WIND
ADVISORY NEAR AND WEST OF I 29...AND EXPANDING OVER MUCH OF THE
AREA DURING THE DAY ON WEDNESDAY.
LAPSE RATES REMAIN STEEP INTO THE DAYTIME...BUT GRADUALLY MODIFY A
BIT MIDDAY WITH WARMER LAYER ALOFT BUILDING IN...WHICH COULD WORK
TO SLOW UP OR EVEN END CONVECTION FROM SOUTHWEST TO NORTHEAST DURING
THE MORNING AND LINGERING INTO THE AFTERNOON. SHOULD KEEP A FAIR
AMOUNT OF CLOUDS AROUND WITH STRONG LOW LEVEL JET...ESPECIALLY
ACROSS SOUTHWEST MINNESOTA INTO NORTHWEST IOWA. IF IT BREAKS
OUT... COULD BE APPRECIABLY WARMER AND GENERATE MORE INSTABILITY
BY WEDNESDAY AFTERNOON...TO CORRELATE WITH APPROACH OF STRONGER
UPPER LIFT FORCING AND CONVERGENT BOUNDARY TOWARD THE JAMES VALLEY
BY LATER IN THE DAY. WOULD CERTAINLY MAINTAIN AT LEAST A SMALL
SEVERE WEATHER THREAT GIVEN THE SHEAR AND INSTABILITY
POTENTIAL...ESPECIALLY FROM THE LOWER JAMES AND BIG SIOUX VALLEY
EASTWARD. TROUGH WILL LIFT PAST WEDNESDAY NIGHT...WITH DYNAMICS
SUPPORTIVE OF HIGHER POPS EAST OF THE JAMES RIVER...AND ESPECIALLY
ACROSS NORTHWEST IOWA. PRECIP THREAT GRADUALLY TAPERING OFF WEST
TO EAST OVERNIGHT...LINGERING IN THE FAR EASTERN CWA INTO THURSDAY
MORNING. UPPER LOW CONTINUES TO DEEPEN AND CLOSE OFF NORTHEAST
OF THE AREA ON THURSDAY...PLACING AREA IN A MORE SUBSIDENT FAVORED
QUADRANT WITH MOISTURE DISPLACED TO THE NORTH/EAST. HAVE TRIMMED
BACK POPS SOMEWHAT...ESPECIALLY THROUGH THE MISSOURI VALLEY...AND
TAKEN TEMPS CLOSER THE 850 HPA MIXING OF DRIER SOLUTIONS.
HANDLING OF THE INTENSE UPPER TROUGH...AND NEXT ONE LATER IN THE
WEEKEND...IS WIDELY VARIED BETWEEN MODELS AND LEADS TO QUITE LOW
CONFIDENCE IN THE OVERALL PATTERN FROM FRIDAY THROUGH SUNDAY.
COULD EVEN FIND THREAT FOR A LITTLE SNOWFALL WITHOUT STRAYING TOO
FAR FROM A COUPLE SOLUTIONS...BUT WAY TOO FAR OUT TO PUT ANY FAITH
IN THE FORECAST. DOES APPEAR AS IF IT WILL BE AN ACTIVE TIME LATER
IN THE WEEKEND...AND WITH THE ABUNDANCE OF CLOUDS AND OR COOLER
AIR IN PLACE...HAVE KEPT NEAR TO A BIT ON THE COOLER SIDE OF
GUIDANCE FOR THE WEEKEND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1155 PM CDT SUN APR 20 2014
VFR CONDITIONS WILL PREVAIL FOR THE REMAINDER OF TONIGHT THROUGH
MONDAY NIGHT. THERE WILL BE SCATTERED SHOWERS AND THUNDERSTORMS
MOVING ACROSS THE FORECAST AREA FOR THE REMAINDER OF TONIGHT...BUT
WILL BE EAST OF THE KHON TAF SITE. TIMED THE CONVECTION FOR THE
KFSD AND KSUX TAF SITES BETWEEN 06Z AND 12Z AND WILL MONITOR FOR
ANY ALTERATIONS. OTHERWISE THERE WILL BE FREQUENT GUSTS BETWEEN 25
AND 30 KNOTS ALONG AND EAST OF THE JAMES RIVER VALLEY DURING THE
LATE MORNING AND AFTERNOON ON MONDAY.
&&
.FIRE WEATHER...
ISSUED AT 406 PM CDT SUN APR 20 2014
A STRONG NORTHWEST WIND WILL DEVELOP THROUGH THE MORNING ON MONDAY
IN A WELL MIXED ATMOSPHERE...LEADING TO DANGEROUS FIRE WEATHER
CONDITIONS. AFTERNOON RELATIVE HUMIDITIES WILL LIKELY DROP TO
BETWEEN 20 AND 25 PERCENT OF THE ENTIRE AREA WITH WINDS AVERAGING
ABOUT 20 TO 30 MPH AND A FEW GUSTS AROUND 35 MPH. SOUTH CENTRAL SD
WILL SEE WINDS MORE IN LINE WITH 15 TO 25 MPH AND WITH EXPECTED
RELATIVE HUMIDITY VALUES ABOVE 20 PERCENT A VERY HIGH FIRE DANGER
WILL BE MAINTAINED. THIS MOST DANGEROUS FIRE WEATHER CONDITIONS
SHOULD BE FROM ABOUT 100 PM TO 700 PM ON MONDAY. DEW POINTS MAY END
UP JUST A BIT HIGHER BUT THE TRENDS SO FAR THIS SPRING HAVE BEEN FOR
THE GUIDANCE TO OVER FORECAST DEW POINTS BY ABOUT 3 TO 6 DEGREES SO
TOOK THIS INTO ACCOUNT.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...FIRE WEATHER WATCH FROM MONDAY AFTERNOON THROUGH MONDAY EVENING
FOR SDZ256>258.
MN...FIRE WEATHER WATCH FROM MONDAY AFTERNOON THROUGH MONDAY EVENING
FOR MNZ900.
IA...FIRE WEATHER WATCH FROM MONDAY AFTERNOON THROUGH MONDAY EVENING
FOR IAZ300-301.
NE...FIRE WEATHER WATCH FROM MONDAY AFTERNOON THROUGH MONDAY EVENING
FOR NEZ249.
&&
$$
UPDATE...
SHORT TERM...08
LONG TERM...CHAPMAN
AVIATION...MJ
FIRE WEATHER...08
AREA FORECAST DISCUSSION
NWS AMARILLO TX
102 AM CDT MON APR 21 2014
.UPDATE...
QUICK UPDATE TO THE FORECAST TO INCORPORATE PATCHY DENSE FOG ACROSS
THE SOUTH CENTRAL TEXAS PANHANDLE. THE LOWEST VISIBILITIES HAVE BEEN
CONFINED TO THE CITY OF AMARILLO AND HAVE BEEN FLUCTUATING BETWEEN
1/2 AND 1/4 MILE. EXPECT THE FOG TO DISSIPATE BY 8 AM AT THE LATEST
ONCE WINDS SHIFT TO THE NORTH AND INCREASE. UPDATED TEXT PRODUCTS
SENT.
&&
.PREV DISCUSSION... /ISSUED 1138 PM CDT SUN APR 20 2014/
AVIATION...
06Z TAF CYCLE
LOW CLOUDS AND FOG HAVE DEVELOPED NEAR OR AT THE AMARILLO TAF SITE
BACK SOUTHEAST INTO THE SOUTHEAST TEXAS PANHANDLE. THE LATEST HRRR
FORECASTING THE LOW CLOUDS AND FOG CONTINUING TO DEVELOP NORTH AND
WEST TOWARD THE GUYMON TAF SITE BY 07Z TO 09Z MONDAY. IFR TO VLIFR
CONDITIONS COULD DEVELOP AT BOTH THE AMARILLO AND GUYMON TAF SITES
BETWEEN 06Z AND 10Z MONDAY. THE HRRR SHOWING THE LOW CLOUDS AND FOG
DISSIPATING FROM WEST TO EAST AWAY FROM BOTH TAF SITES AROUND 10Z TO
12Z MONDAY AS A COLD FRONT AND DRIER AIR PUSHES SOUTH AND EAST. THE
LOW CLOUDS AND FOG NOT EXPECTED TO REACH AS FAR WEST AS THE DALHART
TAF SITE WHERE VFR CONDITIONS PREVAIL THROUGH 06Z TUESDAY. VFR
CONDITIONS ARE EXPECTED TO RETURN TO THE AMARILLO AND GUYMON TAF
SITES BY 10Z TO 12Z MONDAY. WINDS SHOULD BECOME EAST AND SOUTHEAST 5
TO 15 KNOTS AT THE GUYMON AND AMARILLO TAF SITES THROUGH 10Z TO 12Z
MONDAY...THEN SHIFTING TO THE NORTHWEST AND NORTH AS THE COLD FRONT
MOVES THROUGH AND INCREASING TO 15 TO 25 KNOTS WITH HIGHER GUSTS. THE
WINDS WILL VEER AROUND TO THE NORTHEAST AND DIMINISH AFTER 20Z MONDAY
5 TO 10 KNOTS OR LESS. AT THE DALHART TAF SITE...WINDS WILL REMAIN
WEST TO NORTHWEST 5 TO 10 KNOTS THEN SHIFTING TO THE NORTH 15 TO 25
KNOTS WITH HIGHER GUSTS AFTER 10Z TO 12Z MONDAY AFTER THE COLD FRONT
MOVES THROUGH...THEN VEERING AROUND TO THE NORTHEAST AND EAST AFTER
20Z MONDAY 5 TO 15 KNOTS.
SCHNEIDER
PREV DISCUSSION... /ISSUED 1046 PM CDT SUN APR 20 2014/
UPDATE...
CONVECTION HAS PUSHED EAST OF MOST OF THE PANHANDLES LATE THIS
EVENING. A FEW LINGERING SHOWERS ACROSS THE FAR EASTERN TX PANHANDLE
WILL PUSH EAST OF THE AREA BY MIDNIGHT...WITH DRY CONDITIONS EXPECTED
OVERNIGHT. UPDATED FORECAST TO REFLECT THESE TRENDS.
KB
PREV DISCUSSION... /ISSUED 616 PM CDT SUN APR 20 2014/
AVIATION...
00Z TAF CYCLE
SCATTERED CONVECTION ACROSS THE PANHANDLES MAY AFFECT THE THREE TAF
SITES THROUGH 01Z TO 02Z MONDAY. VFR CONDITIONS WILL PREVAIL ALONG
WITH SOUTHWESTERLY TO WESTERLY WINDS BECOMING NORTH BEHIND A COLD
FRONT LATER TONIGHT AND EARLY MONDAY. THE FRONT IS EXPECTED TO MOVE
THROUGH THE DALHART AND GUYMON TAF SITES AROUND 08Z TO 12Z
MONDAY...AND THEN ACROSS THE AMARILLO TAF SITE BY 14Z TO 15Z MONDAY.
NORTHERLY TO NORTHEASTERLY WINDS WILL INCREASE TO AROUND 15 TO 25
KNOTS WITH HIGHER GUSTS BEHIND THE FRONT AND THEN DIMINISHING TO 10
TO 15 KNOTS AFTER 20Z MONDAY.
SCHNEIDER
PREV DISCUSSION... /ISSUED 330 PM CDT SUN APR 20 2014/
DISCUSSION...
ONLY MINOR CHANGES HAVE BEEN MADE TO THE FORECAST. HAVE INCREASED
POPS THIS EVENING ACROSS THE SOUTHEAST HALF OF THE FORECAST AREA...
CLOSER TO PROXIMITY OF INCOMING UPPER-LEVEL JET STREAK...IN REGION
OF GREATER INSTABILITY. POPS AFTER MIDNIGHT HAVE BEEN TRIMMED TO
INCLUDE ONLY FAR EASTERN SECTIONS...AHEAD OF DEPARTING VORTICITY
MAXIMUM.
MONDAY AND TUESDAY EXPECTED TO BE DRY AND MILD. LOW-LEVEL JET
DEVELOPS TUESDAY NIGHT AHEAD OF NEXT MID-LEVEL TROF. WEDNESDAY
AFTERNOON CHANCES FOR STRONG TO SEVERE THUNDERSTORMS HAVE BEEN
INCREASED SLIGHTLY AND SPREAD A BIT FARTHER WEST DUE TO EXPECTED
POSITION OF DRYLINE. WEDNESDAY EVENING POPS HAVE BEEN KEPT IN
EASTERN SECTIONS HAVE ALSO BEEN INCREASED SLIGHTLY...AND HAVE
ALSO BEEN SPREAD A BIT FARTHER WEST.
NO POPS IN REMAINDER OF FORECAST. NO FREEZING TEMPERATURES
EXPECTED. 03
COCKRELL
FIRE WEATHER...
NO ELEVATED OR CRITICAL FIRE WEATHER CONDITIONS ARE EXPECTED
THROUGH TUESDAY. CRITICAL FIRE WEATHER CONDITIONS WILL BE POSSIBLE
ON WEDNESDAY ACROSS THE WESTERN HALF OF THE PANHANDLES. ELEVATED TO
CRITICAL FIRE WEATHER CONDITIONS WILL BE POSSIBLE ON SATURDAY ACROSS
THE WESTERN HALF OF THE PANHANDLES. ELEVATED FIRE WEATHER CONDITIONS
WILL BE POSSIBLE ON SUNDAY ACROSS THE WESTERN TWO THIRDS OF THE
PANHANDLES. 03
&&
.AMA WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
OK...NONE.
&&
$$
09/14
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
1141 PM CDT SUN APR 20 2014
.AVIATION...
SHOWERS AND THUNDER JUST ABOUT TO AN END ACROSS THE AREA...
CERTAINLY FINISHED AT BOTH TEMINALS...AS THE UPPER TROUGH THAT
SPAWNED THEM SHIFTS EWD INTO OKLAHOMA. LINGERING LOW LEVEL
MOISTURE ACROSS THE ROLLING PLAINS AND ERN PANHANDLE WITH SOME
PATCHY LOW CLOUDS NOTED ON SATELLITE WHERE CIRRUS HAS CLEARED.
COULD SEE SOME PERIODS OF MVFR...IF NOT IFR...CIGS AT KCDS BEFORE
A COLD FRONT ARRIVES TOWARD 13Z. ON THE CAPROCK AT KLBB WINDS
ALREADY FROM THE WEST WITH MODEST DRY ADVECTION LIKELY TO KEEP LOW
LEVEL MOISTURE AND LOW CLOUDS EAST OF THE TERMINAL.
&&
.PREV DISCUSSION... /ISSUED 624 PM CDT SUN APR 20 2014/
AVIATION...
UPPER LOW MOVING ACROSS THE PANHANDLE ATTM WITH SCATTERED SHOWERS
AND ISOLATED THUNDER UNDERNEATH IT. CONVECTION SHOULD SHIFT TO THE
EAST OF THE AREA BY 03Z. THREAT OF THUNDER AT EITHER TERMINAL IS
NON-ZERO BUT NOT BIG ENOUGH TO RUN WITH A PREVAILING OR TEMPO
GROUP ATTM. VFR CONDITIONS LIKELY THROUGH THE NIGHT WITH SMALL
CHANCE FOR SOME FOG AND/OR LOW CLOUDS AHEAD OF A COLD FRONT TOWARD
12Z...AGAIN THE CHANCE OF WHICH IS TOO SMALL TO INSERT MENTION
INTO EITHER TAF. FINALLY...WIND SWITCH TO NORTH WITH THE COLD
FRONT MONDAY MORNING.
PREV DISCUSSION... /ISSUED 337 PM CDT SUN APR 20 2014/
SHORT TERM...
VIS SAT SHOWS A LINE OF CU DEVELOPING IN THE WESTERN TX PANHANDLE
AND IS GRADUALLY PUSHING EASTWARD WHILE DEVELOPING SOUTHWARD. A FEW
RETURNS HAVE SHOWED UP ON RADAR OVER PARMER COUNTY WHICH IS RIGHT IN
LINE WITH THIS CU DEVELOPMENT. THIS IS MOST LIKELY ASSOCIATED WITH
THE /DRY/ LINE AS SURFACE OBS INDICATE A SURFACE TROF IN THE
AFOREMENTIONED AREA WITH WESTERLY WINDS AND SLIGHTLY DRIER DEWPOINTS
MOVING IN BEHIND THE TROF. THE DRY LINE WILL CONTINUE WITH ITS
EAST/SOUTHEASTWARD MOVEMENT AS THE UPPER LEVEL LOW TO OUR NORTHWEST
MOVES CLOSER. CURRENT RAP ANALYSIS INDICATES THAT COLDER AIR ALOFT
IS PUSHING IN AND IS INCREASING OUR LAPSE RATES. SCATTERED SKIES ARE
HELPING AID SOME SURFACE HEATING IN TURN HELPING TO SLOWLY ERODE
WHAT CAP IS LEFT. AS CLEARER SKIES MOVE EASTWARD THIS SHOULD HELP
WARM THE SURFACE MORE TO THE POINT OF FULL CAP EROSION. THIS WILL
HELP FIRE CONVECTION MORE QUICKLY AS THE DRYLINE MOVES INTO THE
CENTRAL SOUTH PLAINS AND TX PANHANDLE. FORECAST SOUNDINGS CONTINUE
TO INDICATE THE POTENTIAL FOR STRONG TO SVR CONVECTION WITH CHANCES
INCREASING THROUGH THE AFTERNOON/EVENING EASTWARD. WHILE CAPE THERMO
PROFILES ARE ADEQUATE TO PRODUCE SVR HAIL AND WINDS...0-6KM SHEAR IS
HIGH END MARGINAL TOPPING OUT AT AROUND 40 KTS OVER THE ROLLING
PLAINS AND 35 KTS ALONG THE I27/HWY84 CORRIDOR. I HAVE KEPT
INHERITED POPS BEFORE 00Z WITH SVR MENTION AND INCREASED COVERAGE TO
50 POPS OVER THE ROLLING PLAINS FOR LATER TONIGHT.
PRECIP/CONVECTION CHANCES WILL QUICKLY DIMINISH AS THE DRY
LINE/UPPER LEVEL LOW MOVES EASTWARD AND AS A WEAK FRONT PUSHING INTO
THE AREA TOMORROW MORNING. TEMPS WILL BE WARM IN THE MID 70S TO 80S
TOMORROW AS CAA WILL BE WEAK AND SHORT LIVED DURING THE MORNING AND
SKIES WILL CLEAR MAKING WAY FOR SOLAR HEATING. ALDRICH
LONG TERM...
LITTLE CHANGE FOR THE EXTENDED PORTION OF THE FORECAST THIS GO AROUND.
WE CONTINUE TO LOOK FOR WARMER TEMPS AND A RETURN TO SOUTH BREEZES
TUESDAY AS SHORTWAVE RIDGE BRIEFLY TRANSITS WTX DOWNSTREAM OF A
FAIRLY DEEP TROUGH MOVING ACROSS THE WEST. FAIRLY ROBUST MOISTURE
RETURN IS EXPECTED TUESDAY NIGHT ON THE NOSE OF THE LLJ. THE GFS AND
ECMWF REMAIN IN DECENT AGREEMENT THAT AS THE SHORTWAVE TROUGH
CROSSES THE ROCKIES...A DRYLINE SHOULD DEVELOP ACROSS THE SRN
PLAINS. MODELS ARE STILL IN FLUX WITH THE EAST-WEST POSITION OF
THE DRYLINE BY PEAK HEATING...BUT IT APPEARS LIKELY IT WILL BE
SOMEWHERE IN THE VICINITY OF THE CAPROCK ESCARPMENT. WE CONTINUE
TO CARRY A SLIGHT CHANCE OF TSTMS TO THE EAST OF THE DRYLINE...AND
HAVE BUMPED POPS UP SLIGHTLY INTO THE CHANCE CATEGORY ACROSS THE
NE ZONES. A WEAK COLD FRONT WILL FOLLOW ON THURSDAY...ALTHOUGH IT
MAY NOT PASS THROUGH THE ENTIRE CWA BEFORE LIFTING. ANOTHER LARGE
TROUGH WILL FOLLOW FOR NEXT WEEKEND...ALTHOUGH THERE CONTINUES TO
BE A LOT OF UNCERTAINTY REGARDING THE STRENGTH AND ORIENTATION OF
THE MID-LVL FLOW ACROSS THE SRN PLAINS AND WHETHER OR NOT WE CAN
HOLD ON TO LOW-LVL MOISTURE. DRYLINE ACTIVITY MAY BE POSSIBLE SAT
AND SUN ACROSS ERN ZONES...BUT HAVE MAINTAINED POPS BELOW MENTION
FOR NOW. AFTER A BRIEF COOL DOWN MOST AREAS ON THURSDAY....TEMPS
SHOULD BE A LITTLE ABOVE NORMAL HEADING INTO THE WEEKEND.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 50 74 51 79 52 / 10 10 0 0 0
TULIA 51 76 50 80 55 / 30 10 0 0 0
PLAINVIEW 53 78 51 81 56 / 20 10 0 0 0
LEVELLAND 54 80 54 82 59 / 10 10 0 0 0
LUBBOCK 55 81 56 81 60 / 20 10 0 0 0
DENVER CITY 55 78 55 82 61 / 10 10 0 0 0
BROWNFIELD 54 79 56 83 60 / 10 10 0 0 0
CHILDRESS 58 82 56 82 57 / 50 10 0 0 0
SPUR 58 83 57 82 60 / 40 10 0 0 0
ASPERMONT 60 85 58 83 61 / 40 10 0 0 0
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
07
AREA FORECAST DISCUSSION
NWS AMARILLO TX
1138 PM CDT SUN APR 20 2014
.AVIATION...
06Z TAF CYCLE
LOW CLOUDS AND FOG HAVE DEVELOPED NEAR OR AT THE AMARILLO TAF SITE
BACK SOUTHEAST INTO THE SOUTHEAST TEXAS PANHANDLE. THE LATEST HRRR
FORECASTING THE LOW CLOUDS AND FOG CONTINUING TO DEVELOP NORTH AND
WEST TOWARD THE GUYMON TAF SITE BY 07Z TO 09Z MONDAY. IFR TO VLIFR
CONDITIONS COULD DEVELOP AT BOTH THE AMARILLO AND GUYMON TAF SITES
BETWEEN 06Z AND 10Z MONDAY. THE HRRR SHOWING THE LOW CLOUDS AND FOG
DISSIPATING FROM WEST TO EAST AWAY FROM BOTH TAF SITES AROUND 10Z TO
12Z MONDAY AS A COLD FRONT AND DRIER AIR PUSHES SOUTH AND EAST. THE
LOW CLOUDS AND FOG NOT EXPECTED TO REACH AS FAR WEST AS THE DALHART
TAF SITE WHERE VFR CONDITIONS PREVAIL THROUGH 06Z TUESDAY. VFR
CONDITIONS ARE EXPECTED TO RETURN TO THE AMARILLO AND GUYMON TAF
SITES BY 10Z TO 12Z MONDAY. WINDS SHOULD BECOME EAST AND SOUTHEAST 5
TO 15 KNOTS AT THE GUYMON AND AMARILLO TAF SITES THROUGH 10Z TO 12Z
MONDAY...THEN SHIFTING TO THE NORTHWEST AND NORTH AS THE COLD FRONT
MOVES THROUGH AND INCREASING TO 15 TO 25 KNOTS WITH HIGHER GUSTS. THE
WINDS WILL VEER AROUND TO THE NORTHEAST AND DIMINISH AFTER 20Z MONDAY
5 TO 10 KNOTS OR LESS. AT THE DALHART TAF SITE...WINDS WILL REMAIN
WEST TO NORTHWEST 5 TO 10 KNOTS THEN SHIFTING TO THE NORTH 15 TO 25
KNOTS WITH HIGHER GUSTS AFTER 10Z TO 12Z MONDAY AFTER THE COLD FRONT
MOVES THROUGH...THEN VEERING AROUND TO THE NORTHEAST AND EAST AFTER
20Z MONDAY 5 TO 15 KNOTS.
SCHNEIDER
&&
.PREV DISCUSSION... /ISSUED 1046 PM CDT SUN APR 20 2014/
UPDATE...
CONVECTION HAS PUSHED EAST OF MOST OF THE PANHANDLES LATE THIS
EVENING. A FEW LINGERING SHOWERS ACROSS THE FAR EASTERN TX PANHANDLE
WILL PUSH EAST OF THE AREA BY MIDNIGHT...WITH DRY CONDITIONS EXPECTED
OVERNIGHT. UPDATED FORECAST TO REFLECT THESE TRENDS.
KB
PREV DISCUSSION... /ISSUED 616 PM CDT SUN APR 20 2014/
AVIATION...
00Z TAF CYCLE
SCATTERED CONVECTION ACROSS THE PANHANDLES MAY AFFECT THE THREE TAF
SITES THROUGH 01Z TO 02Z MONDAY. VFR CONDITIONS WILL PREVAIL ALONG
WITH SOUTHWESTERLY TO WESTERLY WINDS BECOMING NORTH BEHIND A COLD
FRONT LATER TONIGHT AND EARLY MONDAY. THE FRONT IS EXPECTED TO MOVE
THROUGH THE DALHART AND GUYMON TAF SITES AROUND 08Z TO 12Z
MONDAY...AND THEN ACROSS THE AMARILLO TAF SITE BY 14Z TO 15Z MONDAY.
NORTHERLY TO NORTHEASTERLY WINDS WILL INCREASE TO AROUND 15 TO 25
KNOTS WITH HIGHER GUSTS BEHIND THE FRONT AND THEN DIMINISHING TO 10
TO 15 KNOTS AFTER 20Z MONDAY.
SCHNEIDER
PREV DISCUSSION... /ISSUED 330 PM CDT SUN APR 20 2014/
DISCUSSION...
ONLY MINOR CHANGES HAVE BEEN MADE TO THE FORECAST. HAVE INCREASED
POPS THIS EVENING ACROSS THE SOUTHEAST HALF OF THE FORECAST AREA...
CLOSER TO PROXIMITY OF INCOMING UPPER-LEVEL JET STREAK...IN REGION
OF GREATER INSTABILITY. POPS AFTER MIDNIGHT HAVE BEEN TRIMMED TO
INCLUDE ONLY FAR EASTERN SECTIONS...AHEAD OF DEPARTING VORTICITY
MAXIMUM.
MONDAY AND TUESDAY EXPECTED TO BE DRY AND MILD. LOW-LEVEL JET
DEVELOPS TUESDAY NIGHT AHEAD OF NEXT MID-LEVEL TROF. WEDNESDAY
AFTERNOON CHANCES FOR STRONG TO SEVERE THUNDERSTORMS HAVE BEEN
INCREASED SLIGHTLY AND SPREAD A BIT FARTHER WEST DUE TO EXPECTED
POSITION OF DRYLINE. WEDNESDAY EVENING POPS HAVE BEEN KEPT IN
EASTERN SECTIONS HAVE ALSO BEEN INCREASED SLIGHTLY...AND HAVE
ALSO BEEN SPREAD A BIT FARTHER WEST.
NO POPS IN REMAINDER OF FORECAST. NO FREEZING TEMPERATURES
EXPECTED. 03
COCKRELL
FIRE WEATHER...
NO ELEVATED OR CRITICAL FIRE WEATHER CONDITIONS ARE EXPECTED
THROUGH TUESDAY. CRITICAL FIRE WEATHER CONDITIONS WILL BE POSSIBLE
ON WEDNESDAY ACROSS THE WESTERN HALF OF THE PANHANDLES. ELEVATED TO
CRITICAL FIRE WEATHER CONDITIONS WILL BE POSSIBLE ON SATURDAY ACROSS
THE WESTERN HALF OF THE PANHANDLES. ELEVATED FIRE WEATHER CONDITIONS
WILL BE POSSIBLE ON SUNDAY ACROSS THE WESTERN TWO THIRDS OF THE
PANHANDLES. 03
&&
.AMA WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
OK...NONE.
&&
$$
11
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
323 AM CDT MON APR 21 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 323 AM CDT MON APR 21 2014
THE MAIN FOCUS THROUGH TONIGHT IS ON THE TIMING OF THE COLD FRONT
PASSAGE AND THE CONVECTION THAT IS EXPECTED TO DEVELOP AHEAD OF IT
TODAY.
SHOWERS AND SOME THUNDERSTORMS CONTINUE ACROSS MUCH OF THE REGION
WHICH IS IN A BROAD CHANNEL OF LOW LEVEL MOISTURE TRANSPORT AHEAD
OF A SURFACE COLD FRONT. THE 21.07Z RAP ANALYSIS SHOWS THAT THE
HIGHEST 0-3KM MUCAPE OF A FEW HUNDRED J/KG IS ACROSS SOUTH
CENTRAL MINNESOTA AND NORTH CENTRAL IOWA WHERE DEW POINTS ARE IN
THE MID TO UPPER 50S AND TEMPERATURES ARE IN THE LOW 60S. 0-6KM
SHEAR IS ALSO WEAK AT 20-30KTS...SO ANY STORMS THAT HAVE
DEVELOPED ARE PULSEY AND COLLAPSE RATHER QUICKLY.
THE 21.00Z NAM/GFS/GEM/ECMWF AND 21.06Z RAP/HRRR/HOPWRF ARE ALL IN
VERY GOOD AGREEMENT WITH THE TIMING OF THE COLD FRONT COMING
THROUGH THE REGION TODAY. CURRENTLY...SURFACE OBS SHOW THAT THIS
FRONT IS IN WESTERN MINNESOTA/EASTERN NEBRASKA. GUIDANCE SUGGESTS
THAT THE FRONT WILL BE INTO NORTHEAST WISCONSIN/FAR SOUTHEAST
MINNESOTA/NORTHEAST IOWA AROUND NOON AND THEN CLEAR OF SOUTHWEST
WISCONSIN BY MID AFTERNOON. INSTABILITY WILL BUILD AHEAD OF THE
FRONT THOUGH THE 21.00Z NAM/GFS AND 21.06Z RAP LIKELY DEVELOP TOO
HIGH OF MUCAPE WITH THEM SHOWING SURFACE DEW POINTS CLIMBING UP TO
THE LOW 60S WHEN THEY WILL LIKELY BE MORE IN THE MID 50S. THERMAL
PROFILES SHOW THAT THIS INSTABILITY IS IN THE 0C TO -20C PORTION
OF THE SOUNDINGS...SO THERE COULD BE SOME SMALL HAIL THAT DEVELOPS
FROM THIS CONVECTION DESPITE 0-6KM SHEAR REMAINING WEAK AT
20-30KT.
ONCE THE FRONT COMES THROUGH...THERE IS A SOLID SLUG OF DRIER AIR
THAT WILL MOVE INTO THE REGION. TEMPERATURES MAY NOT MAKE TOO MUCH
OF AN INITIAL DROP SINCE THE FRONT IS COMING THROUGH DURING THE
MIDDLE OF THE DAY WITH THE DRIER AIR MASS BEHIND THE FRONT
ALLOWING FOR QUICKER WARMING UNDER SUNNY SKIES. TEMPERATURES WILL
PLUMMET TONIGHT WITH THE DRY AIR MASS IN PLACE AND NORTHWESTERLY
LOW LEVEL WINDS KICKING IN. COULD SEE SOME GUSTY WINDS AS WELL
WITH THIS DRY AIR IN THE AFTERNOON WITH SOME 35MPH GUSTS POSSIBLE
IN THE HIGHER TERRAIN OF SE MN/NE IA.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 323 AM CDT MON APR 21 2014
THE MAIN FOCUS IN THE EXTENDED IS ON A BROAD MID LEVEL TROUGH
CURRENTLY ALONG THE WEST COAST WHICH WILL PROPAGATE EAST ALONG THE
US/CANADIAN BORDER FROM THE MIDDLE TO END PORTION OF THE WEEK.
GUIDANCE HAS BEEN IN FAIRLY GOOD AGREEMENT ON THIS SYSTEM THOUGH
THERE ARE SOME MINOR DIFFERENCES THAT ARISE TOWARD THE LATER
PORTION OF THE SYSTEM. CONFIDENCE IS STILL FAIRLY HIGH THAT
PRECIPITATION WILL MOVE IN FROM THE WEST ON WEDNESDAY WITH THE
LEAD WARM AIR ADVECTION BAND FOLLOWED BY THE MAIN MOISTURE CHANNEL
AHEAD OF THE COLD FRONT ON THURSDAY. THERMAL PROFILES STILL DO NOT
SHOW MUCH IN THE WAY OF INSTABILITY BUT DO INCREASE PW VALUES UP
TO AROUND 1-1.50" EARLY ON THURSDAY. BASED ON THIS CONSISTENT
SIGNAL...HAVE UPPED PRECIPITATION CHANCES INTO THE 70-85 PERCENT
RANGE FOR MUCH OF THE REGION WITH TOTAL QPF VALUES EXPECTED TO BE
AROUND AN INCH.
GUIDANCE STARTS TO DEVIATE QUITE A BIT STARTING FRIDAY WITH THE
21.00Z GFS SHOWING A STRONG RIDGE OF HIGH PRESSURE EXTENDING FROM
HUDSON BAY THROUGH THE NORTHERN PLAINS WHILE THE 21.00Z ECMWF IS
WEAKER WITH THIS RIDGE AND KEEPS A LOW LEVEL THERMAL GRADIENT
ACROSS THE REGION ON INTO THE SOUTHERN GREAT LAKES. THE GFS
SOLUTION WOULD BE A COLDER/DRIER ONE FOR US WHILE THE ECMWF
SOLUTION WOULD MEAN A WETTER/SLIGHTLY WARMER SOLUTION THAT STILL
COULD BRING SOME P-TYPE ISSUES IN WITH IT. CURRENTLY...WPC IS
FAVORING THE GFS MORE THAN THE ECMWF BUT TIME WILL TELL. FOR
NOW...HAVE DONE A BLEND WITH SOME PRECIPITATION CHANCES IN THERE
FOR THE WEEKEND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1114 PM CDT SUN APR 20 2014
SHOWERS AND EMBEDDED THUNDERSTORMS ACROSS NORTHERN IOWA...SITUATED
JUST NORTH OF A WARM FRONT ALONG US-20...ARE INCHING THEIR WAY
NORTHWARD TOWARDS THE TAF SITES. ITS POSSIBLE FOR THESE SHOWERS
TO AFFECT THE TAF SITES FROM NOW THROUGH 14-16Z WHEN A COLD FRONT
IS SLATED TO MOVE ACROSS. SINCE CONFIDENCE OF THESE SHOWERS
HANGING AT EITHER TAF SITE FOR MORE THAN 1 OR 2 HOURS IS LOW...
HAVE ONLY WENT WITH A VCSH. ALSO DID NOT INCLUDE THUNDER AS THE
AMOUNT OF LIGHTNING HAS DROPPED OFF QUITE A BIT WITH LOSS OF
INSTABILITY. THERE HAS BEEN SOME BR AROUND THE TAF SITES...ENOUGH
TO KNOCK LSE DOWN TO MVFR. MVFR VISIBILITIES SHOULD BE THE GENERAL
RULE UNTIL COLD FRONTAL PASSAGE. PLAN ON CEILINGS TO STAY VFR.
AFTER THE COLD FRONT PASSES...DRIER AIR COMES IN ON GUSTY
NORTHWEST WINDS TO ENSURE VFR CONDITIONS. THE WINDS COULD GUST
UPWARDS OF 25 KT. PLAN ON THE WIND GUSTS TO DIMINISH AROUND 01Z
WITH LOSS OF DAYTIME HEATING...BUT A 10-15 KT SUSTAINED WIND LOOKS
LIKELY TO PERSIST ASSOCIATED WITH COLD AIR FLOWING IN.
&&
.HYDROLOGY...
ISSUED AT 323 AM CDT MON APR 21 2014
ANYWHERE FROM A TENTH OF AN INCH TO AN INCH AND A HALF OF RAIN
FELL YESTERDAY ACROSS THE REGION WITH SOME ADDITIONAL RAIN FALLING
EARLY THIS MORNING FROM SHOWERS AND THUNDERSTORMS. THIS HAS LEAD
TO A SMALL CLIMB IN AREA RIVERS...PARTICULARLY IN NORTHEAST IOWA
WHERE SOME OF THE HEAVIEST RAIN HAS FALLEN. RAIN WILL COME TO AN
END FROM WEST TO EAST THIS MORNING AND EARLY AFTERNOON AS A COLD
FRONT PUSHES THROUGH. ANOTHER SYSTEM WILL COME IN AROUND MID WEEK
WHICH COULD DROP A WIDESPREAD AREA OF AN INCH OR MORE OF RAIN FROM
WEDNESDAY INTO THURSDAY. THIS WILL LIKELY LEAD TO A SECOND CREST
ON MANY AREA RIVERS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...HALBACH
LONG TERM...HALBACH
AVIATION...AJ
HYDROLOGY...HALBACH
AREA FORECAST DISCUSSION
NWS SAN JOAQUIN VALLEY - HANFORD CA
305 AM PDT MON APR 21 2014
.SYNOPSIS...
FAIR SKIES AND WARM TEMPERATURES WILL CONTINUE THROUGH TODAY AS
WEAK HIGH PRESSURE PREVAILS. A FRONTAL SYSTEM ON TUESDAY WILL BRING
SIGNIFICANT COOLING AND BLUSTERY CONDITIONS TO THE REGION AND A
CHANCE OF LIGHT PRECIPITATION OVER THE NORTHERN PART OF THE
FORECAST AREA. TEMPERATURES WILL CONTINUE COOLER THAN AVERAGE ON
WEDNESDAY BEFORE REBOUNDING A FEW DEGREES AT THE END OF THE WEEK.
&&
.DISCUSSION...
ONE MORE DAY OF ABOVE-NORMAL TEMPERATURES WITH CENTRAL CALIFORNIA
UNDER A RIDGE...THEN A SHARP CHANGE IN THE WEATHER BEGINS TONIGHT
AND CONTINUES THROUGH WEDNESDAY. THE 00Z MODELS ARE IN GOOD
AGREEMENT WITH SLIGHT WARMING TODAY AHEAD OF THE APPROACHING COLD
FRONT...WITH 850-MB TEMPERATURES OVER THE CENTRAL SAN JOAQUIN VALLEY
WARMING ABOUT 0.5-1.0 C. HIGH TEMPERATURES ACROSS THE CENTRAL AND
SOUTHERN SAN JOAQUIN VALLEY SUNDAY WERE MAINLY IN THE LOWER TO MID
80S...AND SHOULD BE IN THE MID 80S TO AROUND 90 TODAY.
THE UPPER-LEVEL LOW WAS LOCATED NEAR 51N/142W THIS MORNING...WEST OF
THE NORTHERN TIP OF VANCOUVER ISLAND. A NARROW FRONTAL BAND EXTENDED
FROM THE WASHINGTON/OREGON COAST SOUTHWEST TO EAST OF HAWAII...WHILE
THE UPPER-LEVEL TROUGH AXIS WAS ALONG 140W. PRECIPITATION AHEAD OF
THE FRONT WILL REACH THE CENTRAL SIERRA NEVADA THIS EVENING AND
SPREAD SOUTH INTO THE FRESNO COUNTY MOUNTAINS OVERNIGHT AS WELL AS
INTO MERCED AND MADERA COUNTIES IN THE CENTRAL VALLEY. RAIN AND SNOW
SHOWERS ARE FORECAST TO MOVE INTO THE TULARE COUNTY MOUNTAINS
TUESDAY...BUT RAIN IS EXPECTED TO REMAIN NORTH OF FRESNO ON THE SAN
JOAQUIN VALLEY FLOOR.
THE MODELS ARE IN AGREEMENT WITH 850-MB TEMPERATURES OVER THE
CENTRAL SAN JOAQUIN VALLEY PLUNGING FROM AROUND 15.5 C THIS
AFTERNOON TO AROUND 4 C TUESDAY AFTERNOON. SNOW LEVELS ARE FORECAST
TO FALL TO AROUND 5500 FEET BY WEDNESDAY MORNING DOWN THE LENGTH OF
THE SOUTHERN SIERRA NEVADA AND THE TEHACHAPI MOUNTAINS. HOWEVER...
THIS APPEARS TO BE A RELATIVELY MOISTURE-STARVED SYSTEM...AND QPF
FOR THE MOUNTAINS IS EXPECTED TO BE LESS THAN A TENTH OF AN INCH...
AND ONLY A FEW HUNDREDTHS ON THE SAN JOAQUIN VALLEY FLOOR.
THE MAIN IMPACT OF THIS STORM WILL BE GUSTY WINDS OVER THE WEST SIDE
OF THE SAN JOAQUIN VALLEY...OVER THE SOUTHERN SIERRA NEVADA CREST
AND ACROSS THE MOUNTAINS AND DESERTS OF KERN COUNTY AS THE COLD
FRONT PUSHES THROUGH. DEPENDING ON HOW MUCH RAIN FALLS AHEAD OF THE
FRONT...BLOWING DUST ON THE WEST SIDE OF THE SAN JOAQUIN VALLEY
COULD BE A CONCERN. BLOWING DUST IS MORE LIKELY IN THE KERN COUNTY
DESERT AND THE INDIAN WELLS VALLEY TUESDAY AND TUESDAY EVENING.
AT THIS TIME...WINDS ARE FORECAST TO ONLY BRIEFLY REACH ADVISORY
LEVELS IN THE KERN COUNTY MOUNTAINS AND DESERT AREAS TUESDAY...AND
REMAIN MAINLY BELOW ADVISORY LEVELS ON THE WEST SIDE OF THE SAN
JOAQUIN VALLEY. BASED ON HOW THE 12Z RUNS OF THE HIGHER-RESOLUTION
NAM-12 AND HRRR HANDLE THE WINDS...ADVISORIES MAY BE NEEDED BUT WILL
LET THE DAY CREW EVALUATE THINGS.
ANOTHER RIDGE IS FORECAST TO BUILD INTO CALIFORNIA FOR NEXT
THURSDAY...BRINGING ANOTHER ROUND OF DRY AND WARMER WEATHER. HIGH
TEMPERATURES NEXT THURSDAY ARE FORECAST TO RECOVER TO NEAR NORMAL.
CENTRAL AND SOUTHERN SAN JOAQUIN VALLEY HIGHS NEXT FRIDAY ARE
FORECAST TO WARM INTO THE UPPER 70S TO LOWER 80S...A FEW DEGREES
ABOVE THE NORMAL FOR LATE APRIL.
THE GLOBAL-COMPOSITE WATER VAPOR LOOP SHOWS THE NEXT UPPER-LEVEL LOW
STRADDLING THE INTERNATIONAL DATE LINE AT 50N. BOTH THE GFS AND THE
ECMWF FORECAST THIS LOW TO IMPACT THE WFO HANFORD WARNING/FORECAST
AREA FRIDAY INTO NEXT WEEKEND. THE GFS IS STRONGER WITH THIS SYSTEM
THAN THE ECMWF...BUT AT THIS TIME IT LOOKS LIKE MAINLY A MOUNTAIN
PRECIPITATION EVENT.
&&
.AVIATION...
MOUNTAIN OBSCURATION AND LOCAL MVFR CONDITIONS IN SHOWERS OVER THE
SOUTHERN SIERRA AROUND YOSEMITE AFTER 06Z TUESDAY. OTHERWISE...VFR
CONDITIONS WILL PREVAIL ACROSS THE CENTRAL CALIFORNIA INTERIOR
DURING THE NEXT 24 HOURS.
&&
.AIR QUALITY ISSUES...
NONE.
&&
.CERTAINTY...
THE LEVEL OF CERTAINTY FOR DAYS 1 AND 2 IS HIGH.
THE LEVEL OF CERTAINTY FOR DAYS 3 THROUGH 7 IS HIGH.
THIS INFORMATION IS PROVIDED AS PART OF A TRIAL PROJECT CONDUCTED
BY THE NATIONAL WEATHER SERVICE SAN JOAQUIN VALLEY - HANFORD.
CERTAINTY LEVELS INCLUDE LOW...MEDIUM...AND HIGH. PLEASE VISIT
WWW.WEATHER.GOV/HNX/CERTAINTY.PHP /ALL LOWER CASE/ FOR ADDITIONAL
INFORMATION AND/OR TO PROVIDE FEEDBACK.
&&
.CLIMATE...
RECORDS
SITE DATE HI_MAX:YEAR LO_MAX:YEAR HI_MIN:YEAR LO_MIN:YEAR
KFAT 04-21 98:2009 50:1900 64:2012 36:1968
KFAT 04-22 96:2012 57:2010 66:2012 33:1968
KFAT 04-23 100:1910 56:1961 62:2012 39:1958
KBFL 04-21 99:2009 57:2010 64:2009 33:1904
KBFL 04-22 98:2012 58:2010 67:2012 34:1920
KBFL 04-23 100:1910 59:1960 62:2012 33:1904
&&
.HNX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
PUBLIC...SANGER
AVN/FW...DCH
SYNOPSIS...SANGER
WEATHER.GOV/HANFORD
AREA FORECAST DISCUSSION
NWS DES MOINES IA
652 AM CDT MON APR 21 2014
...UPDATED AVIATION DISCUSSION...
.SHORT TERM /TODAY/...
ISSUED AT 343 AM CDT MON APR 21 2014
STUBBORN COLD FRONT WILL FINALLY SWING THROUGH THE STATE
TODAY AND BRING SCATTERED SHOWERS AND A FEW THUNDERSTORMS TO THE
FORECAST AREA DURING MUCH OF THE MORNING. FRONT LOOKS TO CREEP INTO
NORTHWEST PORTIONS OF THE FORECAST AREA BY AROUND 14-15Z AND
CONTINUE TO PUSH SOUTHEAST AND CLEAR MUCH OF THE FORECAST AREA BY
AROUND 00Z TUESDAY OR SLIGHTLY SOONER. LEANED TOWARD THE SLOWER
SREF/GFS/ECMWF WRT TO WINDS AND TEMPERATURES TODAY. 21.05Z HRRR IS A
LITTLE TOO FAST WITH THE PRECIP MOVING EAST AND THE 21.03Z HOPWRF IS
LIGHTER ON THE COVERAGE. REGARDLESS...UTILIZED A BLEND OF THE TWO
FOR POPS/WX TRENDS THROUGH MIDDAY TODAY...THEN THE 21.03Z
SREF/21.00Z HIRES-ARW/NMM FOR TRENDS THIS AFTERNOON.
SURFACE LOW LOCATED OVER NORTHWEST IOWA/SOUTHWEST MINNESOTA WITH
COLD FRONT EXTENDING SOUTHWEST INTO NEBRASKA. WEAK AND BROAD LARGE
SCALE FORCING AHEAD THIS COLD FRONT AS WELL AS ISENTROPIC LIFT WILL
CONTINUE TO FEED MOISTURE INTO THE FORECAST AREA THIS MORNING.
INSTABILITY NOT IMPRESSIVE TODAY BUT ENOUGH AVAILABLE TO KEEP
MENTION OF THUNDER. HAVE BULK OF THE HIGHER POPS OVER WESTERN AND
NORTHERN IOWA THROUGH 12-14Z BEFORE SHIFTING FURTHER SOUTHEAST LATE
THIS MORNING. BELIEVE MUCH OF THE PRECIP WILL QUICKLY DISSIPATE PAST
18-20Z OR BE CONFINED TO THE SOUTHEAST CORNER OF THE FORECAST AREA.
HAVE NON-DIURNAL TEMPERATURE TREND MENTIONED ACROSS THE NORTH AS
SHOULD SEE THE CAA DEVELOP LATE THIS MORNING AND INCREASE THROUGH
THE AFTERNOON. 850MB TEMPS DROP TO +4C TO +6C BY 18Z IN THE NORTH.
GUSTY NORTH TO NORTHWEST WINDS BEHIND THE FRONT WITH WINDS ATOP THE
MIXED LAYER INCREASING TO AROUND 25 TO 30 KNOTS. MUCH DRIER AIR MASS
FILTERS INTO THE STATE AS WELL WITH SURFACE DEW POINTS DROPPING INTO
UPPER 30S AND LOWER 40S OVER THE NORTHWEST. RH VALUES DECREASE TO
NEAR 25 PERCENT ACROSS A SMALL WESTERN PORTION OF FORECAST AREA.
THOUGH AN INCREASED FIRE WEATHER DANGER TODAY...HELD OFF ON RED FLAG
WARNING DUE TO CRITERIA NOT BEING MET WIDESPREAD.
.LONG TERM /TONIGHT THROUGH SATURDAY/...
ISSUED AT 343 AM CDT MON APR 21 2014
EARLY IN THE PERIOD...FEW CONCERNS. SYSTEM ON THE WAY OUT BY 00Z
TONIGHT WITH SECONDARY COLD FRONT NOW OVER NORTHERN MN DROPPING
SOUTHEAST ACROSS THE REGION TONIGHT...BRINGING DRIER AND COOLER AIR
INTO THE REGION BY MORNING. DESPITE WARM TEMPS THE PAST FEW DAYS...
MORNING LOWS TONIGHT WILL BE MUCH COOLER WITH MID 30S NORTH TO MID
40S SOUTH. TUESDAY LOOKS LIKE A NICE DAY WITH GENERALLY SUNNY SKIES
AND A FEW FAIR WX CUMULUS DURING THE MID AFTERNOON AS HIGH PRESSURE
DROPS SOUTHEAST THROUGH THE DAY...KEEPING WINDS LIGHT. LITTLE MIXING
TO PROMOTE MUCH WARMING OTHER THAN SUNSHINE...SO WILL STICK WITH
HIGHS IN THE UPPER 50S NORTHEAST AND MID 60S ACROSS THE WEST. MODELS
DIFFER SLIGHTLY ON TIMING OF UPSTREAM WAVE AND EXPECTED WARM AIR
ADVECTION/CLOUDS AND APPROACHING SHOWERS FOR WED. OVERALL...INCREASE
IN CLOUDS EXPECTED LATE DAY WEST TUESDAY WITH SHOWERS NEARING THE
WESTERN BORDER BY 12Z. THOUGH THUNDER MORE LIKELY ACROSS THE HIGH
PLAINS AND NE...DRY AIR OVER IOWA WILL COOL AND DIMINISH INSTABILITY
WHEN INITIAL PUSH OF MOISTURE ARRIVES. MODELS SHOW LITTLE
INSTABILITY UNTIL AFTERNOON WED AND THAT AGAIN IS LESS THAN
YESTERDAYS SOLUTIONS. THUS...HAVE TRIMMED AREAL COVERAGE OF THUNDER
TO ISO WEST IN THE MORNING AND ISO EAST/SCT FAR WEST IN THE PM HOURS
WEDNESDAY WITH THE FIRST REAL SURGE OF THETAE ADVECTION. AS THE
SYSTEM CROSSES THE REGION...CONFIDENCE IN EVOLUTION OF SYSTEM HAS
LESSENED SLIGHTLY. MODELS CONTINUE TO HAVE GENERAL TRENDS SIMILAR...
BUT DETAILS DIFFER. OVERALL THE BETTER INSTABILITY WILL REMAIN WEST
OF THE AREA UNTIL NEARER 00Z THUR...THEN WEAKEN OVERNIGHT PRIOR TO
INCREASING AGAIN FROM LATE MORNING THUR THROUGH 00Z FRI. STILL SOME
CONCERNS ABOUT OVERNIGHT CONVECTION ACROSS SOUTH/CENTRAL SECTIONS
WED NIGHT AS SOME BULK SHEAR COULD AID SVR POTENTIAL. BOTH THE
00Z GFS AND THE 12Z/NEW 00Z EURO NOW SUGGEST THAT THE LOW WILL
TRACK NORTHEAST ACROSS IA NEARLY EXITING OUR FORECAST AREA BY
18Z THUR...KEEPING THE BEST INSTABILITY AND SVR POTENTIAL EAST OF
THE AREA BY THURSDAY AFTERNOON. FOR NOW...WILL CONTINUE TO MONITOR
POTENTIAL BUT OVERALL CHANCES WOULD REMAIN CONDITIONAL ON ANY
BETTER ALIGNMENT OF FORCING AND STRONGER INSTABILITY THURSDAY.
BEYOND THUR AFTERNOON...MORE UNCERTAINTY IS ARISING IN THE
REMAINDER OF THE FORECAST. MODELS HANDLING THE DEPARTURE OF THE
SYSTEM WITH DIFFERING SPEED THUR NIGHT AND FRIDAY DUE TO A
SECONDARY H500 SYSTEM OVER CENTRAL CANADA POTENTIALLY PHASING WITH
THE DEPARTING H500 LOW. BOTH THE GEM/EURO TAKE THE FIRST SYSTEM
EAST QUICKLY ENOUGH TO PREVENT MUCH PHASING WHILE THE GFS HOLDS ON
TO A TROUGH EXTENDING WEST INTO MN. THIS RESULTS IN A FARTHER WEST
RIDGE AXIS OVER CANADA THAT DROPS SOUTH INTO THE NORTHERN PLAINS
AND DRIVES THE JET STREAM FARTHER SOUTH...DIRECTLY NEXT WEEKENDS
STORM SOUTH OF IOWA. THE GEM/EURO SHOW ONLY A SLIGHT DELAY IN
TIMING AND STILL BRING RAIN BACK INTO THE AREA FOR THE WEEKEND.
FOR NOW THE GFS SHOWS TOO DRASTIC A CHANGE FOR SUCH A SMALL H500
FEATURE. DUE TO UNCERTAINTY...WILL CUT BACK ON POP CHANCE AT ONSET
OF PRECIP EVENT NEXT SATURDAY BUT WILL STILL KEEP POP INCREASING
WITH TIME THROUGH SUNDAY. TEMPS WILL HAVE EVEN GREATER UNCERTAINTY
NOW...AS TIED TO CHANGES IN EVOLUTION AND TRACK OF WEEKEND UPPER
AIR PATTERN AND STORM TRACK. NEWEST 21/00Z EURO STILL KEEPS TREND
OF WET WEATHER NEXT WEEKEND...WHILE THE GFS REMAINS DRY. OVERALL
THE EURO TENDS TO PERFORM MORE CONSISTENTLY AFTER FCST 120 HOURS
SO WILL LEAN TOWARD GEM/EURO SOLUTIONS OF WETTER WEATHER SAT/SUN.
AS MENTIONED IN PREVIOUS NIGHTS AFDS...THERE IS A CONSISTENT
SIGNAL OF ENERGY STRETCHING FROM THE NORTH CENTRAL PACIFIC EAST TO
THE PLAINS...WHICH WOULD FAVOR INCLEMENT WEATHER HERE.
&&
.AVIATION...21/12Z
ISSUED AT 650 AM CDT MON APR 21 2014
SHOWER AND ISOLATED THUNDERSTORMS WILL AFFECT THE TAF SITES
THROUGH THE MORNING HOURS. BRIEF MVFR AND POSSIBLY IFR CONDITIONS
ARE POSSIBLE...BUT LOW CONFIDENCE WITH MENTIONING AS THEY WILL
HAVE A SHORT DURATION. OTHERWISE...COLD FRONT SWEEPS ACROSS THE
STATE AND CLEARS SKIES THIS AFTERNOON FROM NORTHWEST TO SOUTHEAST.
INCREASED WINDS THIS AFTERNOON.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...PODRAZIK
LONG TERM...REV
AVIATION...PODRAZIK
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
952 AM CDT Mon Apr 21 2014
...UPDATE TO SYNOPSIS...
.SYNOPSIS...
ISSUED AT 950 AM CDT MON APR 21 2014
Water vapor imagery and 12Z upper air analysis indicate an upper
level shortwave trough transitioning eastward across the Central
Plains. Meanwhile, upper level ridging is shifting eastward across
the Intermountain West. Near the surface, a weak cold front extends
from southeastern Colorado northeast across west central Kansas into
southeastern Nebraska. High pressure is building behind the front
across the Colorado Rockies.
&&
.SHORT TERM...(Today and tonight)
ISSUED AT 317 AM CDT MON APR 21 2014
The main shortwave trough is depicted by the models to move into
eastern Kansas this morning. The RUC model has picked up on the MCV
over central Kansas and moves it southward into northwest Oklahoma
today in the northwesterly flow on the backside of the trough. Model
soundings show instability around 600-800 j/kg of CAPE as a mid
level cold pool moves southeast across western Kansas today. Given
the forcing with the MCV and a nearly uncapped sounding profile this
afternoon over south central Kansas, will add some slight chance
pops for showers and isolated thunder to the forecast.
Things will quiet down fairly quickly late this afternoon and early
evening as a ridge of surface high pressure moves east through the
High Plains. Winds will become light and variable in the evening and
gradually swing around to the southeast and south. Overnight lows
will be the coolest over central Kansas where low to mid 40s are
expected. Lows will drop into the upper 40s to around 50 along the
Colorado border where increasing southerly winds will help keep
temperatures up a few degrees more.
.LONG TERM...(Tuesday through Sunday)
ISSUED AT 414 AM CDT MON APR 21 2014
An upper ridge will be transitioning eastward across the Great
Plains on Tuesday. Surface pressure falls along the lee of the
Rockies and the retreating surface high pressure across the Missouri
valley will create a moisture transport zone over the central High
Plains, effectively causing an increasing in surface and 850 mb dew
points across western and central Kansas. Afternoon heating across
the higher terrain around the Palmer Divide will allow thunderstorms
to form and be steered eastward into this moisture and instability
axis. Some thunderstorms could move into western Kansas through the
evening hours most likely around Syracuse. With a lack of dynamics,
convection should be mainly diurnally driven, and as a result dry
weather is likely through the overnight Tuesday into Wednesday
morning with mild lows. An upper wave will be approaching the
region Wednesday with several impacts. A decent surface pressure
gradient will be in place as much drier air mixes out eastward
though the morning and afternoon. The overall momentum transfer will
probably be negatively influenced by mid level cloud decks indicated
on model soundings and may even prevent a high wind event given 0-1
km mean winds on the order of 35-40 knots. Additionally a set up for
severe storms will exist along and ahead of the dryline as the
atmosphere destabilizes through the morning. Potential for rotating
supercells exist with NAM model suggesting around 2-3 m2/s2 EHI(3km)
with up to round 2000 J/kg of surface based CAPE ahead of the
dryline feature. Good subsidence should follow in behind this
dryline overnight into Thursday morning. Dry and warm conditions
will likely follow into Friday as the next flat upper ridge settle
across the region. Additional thunderstorm chances are in the
forecast later in the weekend and early nextweek associated with
yet another west coast jet carving a trough into the southern
Rockies by the GFS and ECMWF.
&&
.AVIATION...(For the 06Z TAFS through 06Z Monday night)
ISSUED AT 1257 AM CDT MON APR 21 2014
Low level moisture advecting up into southwest Kansas could result
in 2-4 miles in mist along with IFR stratus. There is some
uncertainty as to how widespread it will become. For now will have
a tempo group for lower visibility at Garden City and Dodge City
early this morning with conditions improving to VFR between 10 and
12z. A cold front will move through around sunrise and sweep the
low level moisture out of the area. By this afternoon, some
instability showers could develop in the area around and east of
Dodge City and have added VCSH to the Dodge City TAF for this.
&&
.FIRE WEATHER...
ISSUED AT 414 AM CDT MON APR 21 2014
Elevated fire danger is expected for Tuesday as breezy southerly
winds and dew points in the 20s prevail through the day. A more
significant risk is expected Wednesday as a dryline moves as far
east as highway 283 by afternoon with strong gusty surface winds.
Fire weather watches and eventually red flag warningS may be issued
in the coming forecast shifts especially for areas west of Highway
83 for Wednesday.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 76 45 80 56 / 10 0 0 10
GCK 75 45 82 57 / 10 0 10 10
EHA 74 50 85 57 / 10 0 10 10
LBL 76 48 85 57 / 10 0 0 10
HYS 75 43 80 55 / 80 0 10 20
P28 76 47 80 54 / 30 0 0 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...JJohnson
SHORT TERM...Gerard
LONG TERM...Russell
AVIATION...Gerard
FIRE WEATHER...Russell
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
927 AM EDT MON APR 21 2014
LATEST UPDATE...
UPDATE
.SYNOPSIS...
ISSUED AT 318 AM EDT MON APR 21 2014
LOW PRESSURE MOVING ACROSS WISCONSIN AND LOWER MICHIGAN WILL BRING
LIGHT RAIN TO SW LOWER TODAY AND TONIGHT. THIS IS A VERY SLOW MOVING
SYSTEM AND GIVEN THE DRY AIR ALREADY IN PLACE...WE/RE NOT LOOKING AT
TOO MUCH RAIN...PERHAPS A QUARTER INCH. TEMPERATURES WILL CLIMB INTO
THE LOWER TO MID 70S AGAIN TODAY EXCEPT FOR AREAS NORTH OF US-10
WHERE 60S ARE EXPECTED. COOLER WEATHER CAN BE EXPECTED FOR THE
REMAINDER OF THE WEEK WITH MORE RAIN POSSIBLE THURSDAY INTO FRIDAY.
&&
.UPDATE...
ISSUED AT 925 AM EDT MON APR 21 2014
UPDATED FORECAST TO CUT POPS FOR THIS AFTERNOON BASED ON RADAR AND
LATEST HRRR WHICH SHOWS SHOWERS JUST ENTERING NORTHERN ILLINOIS
ATTM AND NOT ARRIVING UNTIL LATE AFTERNOON.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 318 AM EDT MON APR 21 2014
FORECAST CONCERNS DEAL WITH RAIN CHANCES TODAY AS A SLOW MOVING LOW
CROSSES WISCONSIN AND MICHIGAN.
THE LOW IN WISCONSIN WILL SLOWLY MOVE ACROSS NRN LWR TODAY. AHEAD OF
IT...WARM AIR WITH TEMPS IN THE 70S WILL BE NOTED. THE WARMER AIR
WILL BRING SOME ELEVATED INSTABILITY WITH IT...BUT NOTHING TOO
SIGNIFICANT. MUCAPE AROUND 500 J/KG AND LI/S SLIGHTLY BELOW 0C MAY
BE ENOUGH TO GENERATE A FEW STORMS. KEPT THE CHC OF THUNDER IN THE
GRIDS. FORECAST SOUNDINGS THIS AFTERNOON SHOW THE PRESENCE OF SOME
DRIER AIR IN THE LOWER TROP. THIS MAY RESULT IN SOME GUSTY WINDS AS
SHOWERS/STORMS MOVE ACROSS THE CWA.
THE LOW SHOULD MOVE OVER LAKE HURON BY MIDNIGHT AND COOLER AIR WILL
BEGIN TO FLOW BACK INTO THE CWA AS HIGH PRESSURE BUILDS INTO THE
GREAT LAKES. SUNSHINE WILL RETURN TUESDAY AND WEDNESDAY BUT HIGHS
WILL ONLY BE IN THE LOWER TO MID 50S.
.LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 318 AM EDT MON APR 21 2014
MODELS ARE IN FAIRLY GOOD AGREEMENT IN TRACKING A COLD FRONT THROUGH
THE REGION THU NIGHT. A SOUTHERLY LOW LEVEL JET MOVES IN AHEAD OF
THE COLD FRONT. THAT WILL ACT TO DEVELOP A BAND OF SHOWERS. THESE
SHOWERS WILL CROSS THE FORECAST AREA...WITH MOST LOCATIONS EXPECTED
TO SEE SOME PRECIPITATION. WILL KEEP POPS RELATIVELY HIGH THEN.
SOME INSTABILITY IS SHOWING UP IN THE MODELS WITH THIS RUN...SO WE
MAY NEED TO ADD THUNDER TO THE FORECAST.
BEHIND THE COLD FRONT IT WILL TURN WINDY ON FRIDAY. GUSTS OVER 35M
MPH LOOK LIKELY. AS THE UPPER LOW APPROACHES...SHOWERS SHOULD
DEVELOP ESPECIALLY IN THE AFTERNOON. THE HIGH RES EURO DOES SHOW A
MORE NORTHERLY TRACK TO THE IS UPPER LOW WITH THE 00Z MON RUN. THE
GFS IS STRONGER AND FURTHER SOUTH WITH THIS FEATURE AS COMPARED TO
THE HIGH RES EURO. FORECAST SOUNDINGS SHOW SOME CAPE DURING THE
AFTERNOON. MAY NEED TO ADD THUNDER TO THE FORECAST. SHOWERS LOOK
HIGH BASED GIVEN THE LARGE T/TD SPREAD AT THE SURFACE. I WILL
MAINTAIN THE RISK FOR SHOWERS IN THE FORECAST.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 626 AM EDT MON APR 21 2014
VFR WEATHER TO START THE PERIOD...BUT LATER THIS AFTERNOON AND
INTO TONIGHT WE WILL SEE MVFR CLOUDS/VSBYS AS A COLD FRONT ARRIVES.
SOME INSTABILITY WILL BE AROUND...AND THAT COULD SUPPORT A FEW THUNDERSTORMS.
AS THE MOISTURE BECOMES SHALLOWER TONIGHT...WE MAY SEE SOME ICING
SHOWING UP IN THE MVFR CLOUD DECK.
&&
.HYDROLOGY...
ISSUED AT 1153 AM EDT SUN APR 20 2014
MINOR FLOODING EXISTS ON THE MUSKEGON RIVER AT CROTON AND EVART.
THE DOWNWARD TREND CONTINUES ON ALL AREA RIVERS AND TRIBUTARIES.
WE SHOULD SEE A FEW MORE ADVISORIES DROP OFF THE LIST OVER THE
NEXT 24 HOURS OR SO. HOWEVER...LOCAL IMPACTS MAY STILL BE EVIDENT
OVER THE NEXT SEVERAL DAYS ALONG THE MUSKEGON RIVER.
LIGHT RAIN IS POSSIBLE TONIGHT AHEAD OF A SLOW MOVING COLD FRONT.
BEST CHANCES TONIGHT SHOULD REMAIN ALONG AND NORTH OF HIGHWAY 10.
THE FRONT WILL FINALLY PUSH THROUGH MONDAY AFTERNOON AND THATS
WHEN RAIN IS MORE LIKELY THROUGHOUT THE AREA. PRECIPITATION
AMOUNTS WILL BE RATHER LIGHT AND SHOULD NOT HAVE ANY ADVERSE
AFFECTS ON RIVERS. ANOTHER SHOT OF RAIN WILL MOVE IN LATER IN THE
WORK WEEK BUT IT LOOKS LIKE THE HEAVIEST SHOULD REMAIN WEST OF
LOWER MICHIGAN.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
UPDATE...OSTUNO
SYNOPSIS...93
SHORT TERM...93
LONG TERM...MJS
AVIATION...MJS
HYDROLOGY...JAM
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
746 AM EDT MON APR 21 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 424 AM EDT MON APR 21 2014
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW A SPLIT FLOW
REGIME ACRS THE CONUS WITH A STRONGER W-E POLAR BRANCH FLOW NEAR THE
CNDN BORDER TO THE N OF A WEAKER SRN BRANCH OVER THE SCENTRAL
STATES. SHRTWV RDG EMBEDDED IN THE POLAR BRANCH AND OVER NE MN/NW
ONTARIO AS WELL AS VERY DRY AIR SHOWN ON THE 00Z INL/MPX RAOBS ARE
BRINGING DRY WX TO UPR MI THIS MRNG EXCEPT OVER FAR SRN MENOMINEE
COUNTY...WHERE SOME ISOLD -SHRA ARE STILL PRESENT ON THE NRN EDGE OF
RIBBON OF DEEPER MSTR STRUNG W-E THRU THE CENTRAL LKS AND SAMPLED BY
THE FAIRLY MOIST 00Z GRB RAOB. MORE WDSPRD SHRA/EMBEDDED TS ARE
PRESENT OVER SW WI/FAR SE MN UNDER DEEPER MSTR/SOME UPR DVGC AHEAD
OF DISTURBANCE ON THE NRN EDGE OF SRN BRANCH FLOW. ALTHOUGH COLDER
CLOUD TOPS ARE EXPANDING TOWARD THE WI BORDER TO THE NE OF THESE
SHOWERS...THE LOWER LVL W FLOW OF VERY DRY AIR FM THE DIRECTION OF
MPX IS LIMITING THE N SPREAD OF THE SHRA LOCATED JUST S OF THAT RAOB
SITE. OTRW...SOME LOCALLY DENSE FOG HAS FORMED OVER THE CENTRAL/ERN
CWA AS THE DRIER AIR ALOFT MOVED OVER LOCATIONS THAT DID NOT SEE
SGNFT LLVL DRYING YDAY AFTN. OVER THE W WHERE SFC DEWPTS MIXED OUT
AS LO AS 25-30 AT IWD ON SUN AND TEMPS ARE STILL ABV 32 AT MOST
SPOTS...THERE IS LTL IF ANY FOG. A MUCH STRONGER SHRTWV IN THE POLAR
BRANCH FLOW IS NEAR LK WINNIPEG AND MOVING STEADILY TO THE E. THERE
HAVE BEEN SOME SHOWERS AND EVEN SOME LGT STRIKES IN MANITOBA RIGHT
UNDER THE STEEPER LAPSE RATES CLOSE TO THE CORE OF THIS DISTURBANCE.
BUT SINCE THIS SHRTWV IS CUTOFF FM THE MOISTER AIRMASS TO THE S...
THERE IS ONLY A NARROW BAND OF LIGHT SHOWERS ALONG ITS ATTENDANT
COLD FNT MOVING THRU NW MN EARLY THIS MRNG.
MAIN FCST CONCERNS IN THE SHORT TERM INVOLVE FOG EARLY THIS MRNG AND
THEN PCPN CHCS LATER TODAY/TNGT AS POLAR BRANCH SHRTWV/ATTENDANT
COLD FNT IMPACT UPR MI.
TODAY...EXPECT LOCALLY DENSE FOG TO PERSIST EARLY THIS MRNG OVER THE
SE HALF OF THE CWA...BUT INCRSG HI CLDS SHOULD LIMIT THE POTENTIAL
FOR WDSPRD DENSE FOG. WL ISSUE AN SPS TO ALERT THE PUBLIC TO LOCALLY
REDUCED VSBYS. SHRTWV NEAR LK WINNIPEG IS FCST TO MOVE E THRU NW
ONTARIO AND DRAG IT ATTENDANT COLD FNT ACRS UPR MI THIS AFTN. SINCE
BULK OF DPVA/DEEP LYR QVECTOR CNVGC WL REMAIN TO THE N AND JUST
BRUSH THE NRN LAND CWA...SUSPECT ONLY ISOLD-SCT SHOWERS WL ACCOMPANY
THE FROPA. ALMOST ALL THE MODELS THAT WERE SHOWING A GREATER
INTERACTION BTWN THIS SHRTWV/DEEPER MSTR TO THE S AND SGNFT
EXPANSION OF THIS MSTR/SHOWERS INTO UPR MI HAVE RETREATED A BIT FM
THIS FCST...A REASONABLE TREND CONSIDERING THE VERY DRY NATURE OF
THE 00Z MPX RAOB AND LACK OF SGNFT BACKING OF THE UPR FLOW FM THE W
THRU THE DAY. THE 00Z HI RES CNDN MODEL SHOWS THE HEAVIER PCPN
OVERSPREADING MOST OF UPR MI ALONG WITH THE MOST UNSTABLE MIXED LYR
CAPES AOA 1000 J/KG. FCST SDNGS FM THIS MODEL SHOW FAIRLY IMPRESSIVE
MOISTENING THRU THE LOWER TROP WITH SFC DEWPTS RISING TO ARND
55...WHICH DOES NOT SEEM RSNBL IN THE ABSENCE OF A DEEPER SW FLOW.
THE 00Z NAM SHOWS MORE MODEST MOISTENING/DESTABILIZATION OVER THE
SCENTRL. WL CARRY THE HIER CHC POPS THIS AFTN WHERE THIS MODEL SHOWS
THE GREATER INSTABILITY UP TO 700-800 J/KG OVER THE SCNTRL. INCLUDED
A SCHC OF TS IN THIS AREA AS WELL GIVEN ARRIVAL OF COLD FNT DURING
PEAK HEATING TIME THAT WL PUSH TEMPS WELL ABV NORMAL AGAIN IN THE
PRESENCE OF H85 TEMPS NOT FAR FM 10C AND AWAY FM THE MODERATING
INFLUENCE OF THE LKS. COOLER AIR WL ARRIVE OVER THE W LATER IN THE
DAY FOLLOWING THE FROPA.
TNGT...NW FLOW WITH H925 WINDS UP TO 25-35 KTS IN THE WAKE OF THE
COLD FROPA WL DRIVE COLDER AIR BACK INTO THE UPR LKS TNGT. MODELS
SHOW H85 TEMPS SINKING AS LO AS -7 TO -8C OVER THE W BY 12Z TUE.
WHILE THIS INCOMING AIRMASS WL NOT BE COLD ENUF FOR LK EFFECT
PCPN...MODELS DO SHOW SOME LLVL MOISTENING BLO STRENGTHENING
SUBSIDENCE INVRN ARND H85 UNDER THE LARGE SCALE QVECTOR DVGC LEFT IN
THE WAKE OF DEPARTING SHRTWV. GOING FCST SHOWS SOME DRIZZLE/FRZG
DRIZZLE OVER THE HIER TERRAIN WITH MOISTENING/INVRN BASE BLO THE
DGZ. THIS FCST SEEMS RSNBL...BUT DID ADD SOME FLURRIES AS WELL.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 543 AM EDT MON APR 21 2014
SFC TEMPS SHOULD WARM QUICKLY TUESDAY MORNING...LIMITING THE
POTENTIAL FOR FREEZING DRIZZLE. WILL STILL KEEP DRIZZLE GOING GIVEN
THE LIMITED LIKELIHOOD OF ICE CRYSTALS IN THE SOUNDING. OTHERWISE
COOL N-NW WINDS WILL BE THE RULE...WITH 850MB TEMPS IN THE -6 TO -8C
RANGE HELPING TO KEEP MAX SFC TEMPS TUESDAY IN THE UPPER 30S TO MID
40S OVER MUCH OF THE CWA.
DRY HIGH PRESSURE OVERHEAD TUESDAY NIGHT INTO WEDNESDAY WILL RESULT
IN NEARLY CALM WINDS WEDNESDAY MORNING. WITH FEW IF ANY CLOUDS
AROUND AND PW VALUES FALLING TO AROUND 45 PERCENT OF NORMAL /0.25IN/
SHOULD ALLOW TEMPS TO FALL INTO THE 20S TUESDAY NIGHT/WEDNESDAY
MORNING.
PLENTY OF UNCERTAINTY REMAINS WITH OUR END OF THE WEEK SYSTEM. WHILE
POPS HAVE BEEN INCREASED AND MUCH OF THE FOCUS FOR MODERATE TO HEAVY
PRECIP REMAINS OVER THE W HALF OF UPPER MI...THE 21/00Z RUN OF THE
ECMWF HAS BACKED AWAY FROM THE DEEPER MORE WRAPPED UP SFC LOW THAT
IT/S 20/12Z RUN INDICATED. STILL...ALL INDICATIONS ARE THAT 0.5-1IN
OF LIQUID WILL BE POSSIBLE NEAR AND W OF A LINE FROM MQT TO MNM
THURSDAY INTO THURSDAY NIGHT. THE ECMWF ENSEMBLES HAVE 30-40 PERCENT
CHANCE OF SEEING 1IN OR MORE OVER THE W HALF. GIVEN THAT MUCH OF THE
SYSTEM IS AROUND 84HRS OR MORE INTO THE FUTURE...WILL CONTINUE WITH
A MORE BROAD/AVERAGED SOLUTION AT THIS POINT.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 727 AM EDT MON APR 21 2014
ANY LINGERING FOG AT SAW WL BURN OFF QUICKLY THIS MRNG WITH DAYTIME
HEATING. EVEN THOUGH A COLD FNT WL SWING THRU UPR MI TODAY...THE
AIRMASS WL BE TOO DRY FOR ANY SGNFT SHRA ACTIVITY. THE BEST CHC FOR
A FEW -SHRA WL BE AT SAW...AS THE LATER ARRIVAL OF THE FNT WL BE IN
BETTER PHASE WITH DAYTIME HEATING. GUSTY NW WINDS THAT WL APRCH 30
KTS AT THE MORE EXPOSED CMX LOCATION TNGT BEHIND THE FROPA WL DRAW
MUCH COLDER AIR AS WELL AS SOME LO CLDS INTO THE UPR LKS. THE BEST
CHC FOR IFR CONDITIONS WL BE AT IWD AND ESPECIALLY CMX...PLACES THAT
WL EXPERIENCE THE SHARPEST UPSLOPE WIND COMPONENT.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 424 AM EDT MON APR 21 2014
LIGHT WINDS UNDER 15 KTS THIS MORNING ASSOCIATED WITH WEAK HIGH
PRESSURE RIDGE WILL SHIFT TO THE NW LATE TODAY/THIS EVENING
FOLLOWING A COLD FRONTAL PASSAGE AND INCREASE UP TO 25-30 KTS
TONIGHT AS MUCH COLDER AIR INVADES THE UPPER LAKES. NOT OUT OF THE
QUESTION THERE COULD BE SOME GALES OVER PORTIONS OF THE EAST HALF OF
THE LAKE UNDER THE SHARPER GRADIENT/STRONGEST LOW LEVEL WINDS.
MENTIONED SOME GALE FORCE GUSTS UP TO 35 KTS OVER THE ECENTRAL FOR
NOW. THESE STONG WINDS WILL DIMINISH TUE THRU WED AS A HI PRES RIDGE
AND WEAKER PRES GRADIENT MOVE OVER THE AREA. AS ANOTHER LOW PRESSURE
SYSTEM APPROACHES FROM THE PLAINS LATER IN THE WEEK AND THE GRADIENT
SHARPENS AGAIN...INCREASING SE WINDS WILL SHIFT TO THE NE. DEPENDING
ON THE TRACK AND INTENSITY OF THIS LO...THERE COULD BE AT LEAST A
PERIOD OF GALE FORCE WINDS.
&&
.HYDROLOGY...
ISSUED AT 1202 AM EDT MON APR 21 2014
HIGHEST SNOW DEPTH REPORTED YESTERDAY MORNING OF 32IN AT MOHAWK WAS
ABLE TO DROP DOWN TO 28IN BY LATE EVENING. AT THE OTHER END OF THE
SPECTRUM...SEVERAL SITES FROM IWD THROUGH ISQ WERE REPORTING LITTLE
TO NO SNOW. TODAY WILL BE ANOTHER DAY OF MELTING...AS HIGH
TEMPERATURES JUMP INTO THE 50S AND LOW 60S FOR MUCH OF THE AREA. THE
MELT WILL SLOW TUESDAY-TUESDAY NIGHT OVER N UPPER MI AS COLD N-NNW
WINDS KEEP TEMPS TOPPING OUT IN THE 30S AND LOW 40S TUESDAY. AS FOR
FURTHER OUT...TEMPERATURES WILL RETURN TO NEAR NORMAL VALUES
TEMPORARILY WEDNESDAY BEFORE FALLING BACK INTO THE 30S AND 40S
THROUGH THE UPCOMING WEEKEND.
WILL CONTINUE TO NOTICE SIGNIFICANT STREAM/RIVER RISES OVER THE NEXT
FEW DAYS. UNSETTLED WEATHER WILL RETURN FROM THURSDAY THROUGH
FRIDAY...ADDING TO THE RUNOFF. AT THIS POINT THE BEST CHANCE OF
SIGNIFICANT PRECIPITATION LOOKS TO BE OVER THE W HALF OF UPPER
MI...AND SPECIFICALLY THE KEWEENAW PENINSULA WHERE 0.75-1IN OF
LIQUID WILL BE POSSIBLE BY FRIDAY AFTERNOON. WE WILL CONTINUE TO
REFINE THE FCST AS THE TIME NEARS.
SO FAR THE LOCATIONS EXPERIENCING SIGNIFICANT RISES HAVE BEEN
ALSTON/ALSM4/ ON THE STURGEON RIVER...ROCKLAND/RKLM4/ ON THE
ONTONAGON RIVER...AND TO A LESSER EXTENT THE HYDE/FRDM4/ ON THE FORD
RIVER.
WIDESPREAD FLOODING IS NOT FORESEEN AT THIS TIME. HOWEVER...ANY
RIVER THAT HAS ICE REMAINING ON IT...ESPECIALLY THE ESCANABA RIVER
IN DELTA COUNTY...COULD EXPERIENCE AN ICE JAM WITH THE RISING RIVER
LEVELS THIS WEEK. THOSE LIVING AROUND RIVERS...CREEKS...AND STREAMS
SHOULD MONITOR BOTH RIVER LEVELS AND ICE CONDITIONS. ICE JAMS CAN
FORM AND BREAK QUICKLY...RESULTING IN RAPIDLY FLUCTUATING RIVER
LEVELS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...KF
AVIATION...KC
MARINE...KC
HYDROLOGY...KF
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
654 AM CDT MON APR 21 2014
.UPDATE...
ISSUED AT 644 AM CDT MON APR 21 2014
UPDATED TO INCLUDE 12Z AVIATION DISCUSSION BELOW.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 333 AM CDT MON APR 21 2014
MAIN CONCERN IN THE SHORT TERM IS THE CONVECTION CURRENTLY OCCURRING
ACROSS THE AREA... AND HOW IT WILL EVOLVE THROUGH THE MORNING HOURS.
LATEST SURFACE ANALYSIS SHOWS A TIGHT DEWPOINT GRADIENT FROM WEST
CENTRAL MINNESOTA THROUGH WEST CENTRAL WISCONSIN... ACTING AS A WARM
FRONT OF SORTS... WITH THE THERMAL GRADIENT A BIT FARTHER NORTH AND
ALSO TO THE WEST ALONG THE SURFACE TROUGH. SPC MESOANALYSIS MUCAPE
SHOWS VALUES OF 250-500 J/KG COINCIDENT WITH THE AREA OF ACTIVITY
CURRENTLY OVER THE AREA... LINING UP FAIRLY WELL WITH THE RAP
ANALYZED 850MB THETA-E RIDGE AHEAD OF THE SURFACE FRONT AND
SHORTWAVE APPARENT IN WATER VAPOR IMAGERY. THINGS ARE EXPECTED TO
CONTINUE TO SHIFT EAST THIS MORNING... WITH MOST OF THE ACTIVITY
EAST OF THE FORECAST AREA AFTER 15Z. HOWEVER... UNTIL THAT TIME WE
WILL SEE SOME LOCAL DOWNPOURS AND PEA-SIZED HAIL WITH THE STORMS
THAT ARE MOVING THROUGH THE AREA. BY 18Z WE SHOULD SEE CLEARING
QUICKLY WORKING ITS WAY FROM WEST TO EAST ACROSS THE FORECAST
AREA... WITH STRONG NORTHWEST WINDS... PARTICULARLY OVER WEST
CENTRAL AND SOUTH CENTRAL MINNESOTA. THE COMBINATION OF STRONG WINDS
AND RELATIVE HUMIDITY VALUES IN THE 20S THIS AFTERNOON WILL RESULT
IN ELEVATED FIRE DANGER POTENTIAL FOR FROM WEST CENTRAL INTO SOUTH
CENTRAL MINNESOTA... SO WILL CONTINUE THE FIRE WEATHER WATCH FOR
THAT AREA. HIGH PRESSURE WILL BUILD OVER THE REGION TONIGHT... WITH
WINDS QUICKLY DYING OFF DURING THE EVENING HOURS... AND COOLER
TEMPERATURES MOVING BACK INTO THE AREA... MAKING FOR LOWS IN THE 30S
AND PERHAPS BELOW FREEZING IN OUTLYING AREA.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 333 AM CDT MON APR 21 2014
TRENDS IN THE LONG TERM CONTINUE TO INDICATE A FAIRLY ACTIVE
MIDWEEK...FOLLOWED BY A COOLING TRNED THAT WILL LAST THROUGH NEXT
WEEKEND.
HIGH PRESSURE BEGINS THE LONG TERM FOR TUESDAY. IT SHOULD BE A
RATHER PLEASNT DAY WITH LIGHT WINDS...AND MILD TEMPERATURES.
THE NEXT WESTERN CONUS TROUGH DIGS SOUTHEAST AND BEGINS TO AFFECT
THE AREA LATE TUESDAY NIGHT. RETURN FLOW AND LLJ INTENSIFIES
OVER THE EASTERN DAKOTAS LATE TUESDAY NIGHT. THIS WILL DEVELOP AT
LEAST SOME WIDELY SCATTERED CONVECTION IN THE EASTERN
DAKOTAS...SPILLING EAST INTO WEST CENTRAL MN LATE. STEEPER LAPSE
RATES MOVE INTO THE WEST DURING THE DAY WEDNESDAY...WITH THE
THREAT OF ISOLATED CONVECTION EXPECTED. THE MORNING ACTIVITY WILL
SPREAD EAST INTO WESTERN WISCONSIN WITH REDEVELOPMENT AGAIN TO THE
WEST INTO THE AFTERNOON. THE BETTER INSTABILITY WORKS EAST WITH
TROUGH WEDNESDAY NIGHT INTO THURSDAY. AREA OF STEEP LAPSE RATES
LIFT NORTH ACROSS AT LEAST THE SOUTHERN HALF OF THE AREA AHEAD OF
THE SURFACE LOW WHICH IS PROGGED TO MOVE SOUTH OF THE CWA...ALONG/NEAR
THE MN/IA BORDER. STILL SEE SOME ELEVATED HAIL POSSIBILITIES LATER
WEDNESDAY NIGHT AND THURSDAY MORNING.
MODEL DISCREPANCIES REMAIN AS TO HOW QUICKLY THE UPPER LOW MOVES
EAST OF THE AREA. THE 00Z ECMWF IS MOST PROGRESSIVE WITH THE SYSTEM
AND DROPS SOME COLDER AIR SOUTH OVER THE AREA INTO THE WEEKEND.
THE 00Z GFS IS SLOWER AND MUCH MORE AMPLIFIED WITH THE SYSTEM. IT
EVENTUALLY DROPS 85H TEMPERATURES CLOSE TO MINUS 12C ONCE AGAIN BY
SATURDAY MORNING. THIS MAY BE OVERDONE...BUT IT DOES APPEAR WELL
BELOW NORMAL TEMPERATURES ARE ONCE AGAIN IN STORE WELL INTO THE
WEEKEND.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 644 AM CDT MON APR 21 2014
WITH THE EXCEPTION OF THE ACTIVITY CURRENTLY MOVING THROUGH THE
AREA... THE FORECAST PERIOD LOOKS FAIRLY QUIET WITH VFR
CONDITIONS. STRONG NORTHWEST WINDS BY LATE THIS MORNING THROUGH
THIS AFTERNOON WILL BE THE ONLY OTHER ITEM OF NOTE. LATEST SURFACE
ANALYSIS SHOWS COLD FRONT THROUGH ABOUT HALF OF THE AREA... AND
CURRENT TRENDS AND LATEST RAP SHOW IT MOVING THROUGH THE REMAINDER
OF THE AREA BY THE END OF THE MORNING. THIS WILL WORK TO PUSH THE
PCPN OUT AND ALLOW SUNSHINE TO BECOME PREVALENT FROM WEST TO EAST
DURING THE MORNING HOURS. THERE ARE SOME LOW CLOUDS TRYING TO DROP
SOUTH THROUGH NORTH DAKOTA AT THE CURRENT TIME... AND INDICATIONS
ARE THAT THEY SHOULD MAKE IT TO NEAR KAXN BEFORE THEY ERODE AND
STOP THEIR FORWARD PROGRESS. OTHERWISE... LOOK FOR SURFACE RIDGING
TO STEADILY BUILD LATER TODAY INTO TONIGHT... WHICH WILL WORK TO
KNOCK DOWN THE WINDS DURING THE EVENING HOURS.
KMSP...MAIN UNCERTAINTY IS IN THE FIRST HOUR OR TWO OF THE
FORECAST AND WHETHER ANY ADDITIONAL SHRA AND/OR THUNDER MANAGES TO
IMPACT THE AREA. THERE ARE A COUPLE OF LONE SHRA STILL TO THE WEST
RIGHT ALONG THE EXTENSION OF THE UPPER WAVE AND A SECONDARY
SURFACE BOUNDARY ASSOCIATED WITH THE COLD FRONT. ALLOWED FOR A
VCSH THROUGH 1330Z TO ACCOUNT FOR THIS POSSIBILITY. OTHERWISE... WE
SHOULD SEE VFR CONDITIONS WITH GENERALLY SKC AFTER 16Z. NORTHWEST
WINDS WILL GUST AOA 25 KT FOR MUCH OF THE AFTERNOON BEFORE DYING
OFF THIS EVENING AS THE SURFACE HIGH MOVES INTO THE AREA.
/OUTLOOK FOR KMSP/
TUESDAY AFTERNOON...VFR. VARIABLE WIND 5 KT OR LESS BECOMING
SOUTHEAST 5 TO 10 KT.
TUESDAY NIGHT AND WEDNESDAY...MVFR CEILINGS EXPECTED WITH MVFR
VISIBILITIES POSSIBLE ALONG WITH A CHANCE OF RAIN. SOUTHEAST WIND
10 TO 20 KT WITH HIGHER GUSTS.
WEDNESDAY NIGHT...MVFR CEILINGS AND VISIBILITIES EXPECTED... IFR
POSSIBLE WITH RAIN LIKELY. SOUTHEAST WIND 15 TO 20 KT.
THURSDAY...MVFR CEILINGS AND VISIBILITIES EXPECTED EARLY WITH A
CHANCE OF RAIN. SOUTH WIND 10 TO 20 KT SHIFTING WEST.
THURSDAY NIGHT...VFR. WEST WIND 5 TO 15 KT.
FRIDAY...MVFR CEILINGS AND VISIBILITIES POSSIBLE WITH A CHANCE OF
RAIN. WEST WIND 5 TO 15 KT BECOMING NORTHWEST.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...RED FLAG WARNING FROM 1 PM THIS AFTERNOON TO 7 PM CDT THIS
EVENING FOR MNZ047-054>056-064-065-073>075-082-083-091-092.
WI...NONE.
&&
$$
UPDATE...
SHORT TERM...TRH
LONG TERM...DWE
AVIATION...
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1003 AM CDT MON APR 21 2014
.UPDATE...
ISSUED AT 1003 AM CDT MON APR 21 2014
UPDATED THE FORECAST TO INCREASE CLOUD COVER OVER THE
SOUTHEASTERN CWA THIS MORNING BASED ON THE TRAJECTORY OF LOW
STRATUS ROTATING SOUTHEAST ACROSS WESTERN AND CENTRAL NORTH
DAKOTA. STRONG SYNOPTIC SUBSIDENCE OVERSPREADING THE REGION SHOULD
ERODE THIS CLOUD DECK BY EARLY AFTERNOON. OTHERWISE...THE
REMAINING FORECAST ELEMENTS ARE IN GOOD SHAPE. THE UPDATED
PRODUCTS HAVE BEEN SENT.
UPDATE ISSUED AT 625 AM CDT MON APR 21 2014
ONLY CHANGES TO FORECAST WERE TO POPULATE WITH LATEST HOURLY
OBSERVATIONS. TEMPS WERE RUNNING A LITTLE COLDER THAN FORECAST IN
A FEW LOCATIONS. OTHERWISE...LOW STRATUS CONTINUES TO SLOWLY PUSH
SOUTHWARD WHICH IS HANDLED WELL IN FORECAST.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 348 AM CDT MON APR 21 2014
NO MAJOR FORECAST HIGHLIGHTS IN THE SHORT TERM PERIOD.
CURRENTLY...QUASI-ZONAL FLOW ACROSS THE NORTHERN PLAINS WITH A
STRONG EMBEDDED S/WV TROUGH PUSHING EAST ALONG THE INTERNATIONAL
BORDER...NOW CENTERED NEAR TO EAST OF LAKE WINNIPEG. WRAP AROUND
MOISTURE IN THE FORM OF LOW LEVEL STRATUS SURGING SOUTH AND EAST
ACROSS MY NORTHERN COUNTIES THE PAST COUPLE OF HOURS. AT THIS TIME
DO NOT ANTICIPATE ANY PRECIPITATION ASSOCIATED WITH THE STRATUS.
WILL CONTINUE TO MONITOR.
LOW BKN-OVC CLOUDS WILL CONTINUE TO MOVE ACROSS NORTHWEST AND
NORTH CENTRAL NORTH DAKOTA NOW THROUGH 10Z...EVENTUALLY DEPICTED
BY BOTH THE RAP AND 00Z/06Z NAM TO PUSH AS FAR SOUTH AS BISMARCK
AND JAMESTOWN 10-14Z. AFTERWARDS...STRATUS SHOULD DISSIPATE/BURN
OFF BY THE EARLY AFTERNOON. THE MORNING CLOUDS COUPLED WITH CAA
THE PAST SEVERAL HOURS WILL RESULT IN HIGH TEMPERATURES TODAY IN
THE 50S ALONG TO NORTH AND EAST OF THE MISSOURI RIVER...60S SOUTH
AND WEST OF THE MISSOURI.
RETURN FLOW/WAA TONIGHT AS AN UPPER LEVEL RIDGE OF HIGH PRESSURE
AMPLIFIES ACROSS THE ROCKIES TODAY THEN PROPAGATES EAST INTO THE
HIGH PLAINS TONIGHT.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 348 AM CDT MON APR 21 2014
ACTIVE PERIOD EXPECTED WITH STRONG STORM SYSTEM APPROACHING THE
REGION TUESDAY NIGHT. LARGE SURFACE LOW INITIALLY CENTERED OVER
CENTRAL MONTANA 00Z WEDNESDAY TRANSITIONS TO DUAL SURFACE LOWS
OVER SOUTHEASTERN SASKATCHEWAN AND SOUTHEAST MONTANA BY 12Z WED AS
SHORTWAVE/90KT H250 JET STREAK ROTATE AROUND PARENT UPPER LOW.
BREEZY TO WINDY EAST/SOUTHEAST WINDS WILL OCCUR ALSO WITH TIGHT
SURFACE GRADIENT AND 850MB WINDS TO 45KTS LATE TUESDAY AND TUESDAY
NIGHT. SPC CONTINUES TO INCLUDE THE WESTERN HALF OF THE STATE IN
GENERAL THUNDERSTORM AREA WITH MODELS INDICATING LOW CAPE NUDGING
INTO THIS REGION ALONG WITH H7-H5 LAPSE RATES APPROACHING 8C/KM
TUESDAY NIGHT AHEAD OF THE COLD FRONT. MODELS CONTINUE TO SHOW
HIGHEST QPF ACROSS NORTH AND EAST AS DRY SLOT IS MORE OF A FACTOR
ACROSS WESTERN AND SOUTHERN AREAS. WEDNESDAY NIGHT INTO THURSDAY
THE CLOSED UPPER LOW AND ASSOCIATED SURFACE LOW MOVE ACROSS THE
NORTHERN PLAINS. MODEL DIFFERENCES INCREASE WITH THIS FEATURE WITH
THE GFS A LITTLE FASTER AND FARTHER SOUTH COMPARED TO ECMWF. BOTH
MODELS...HOWEVER...BRING SUB 0C H850 AIR ACROSS THE STATE IN
NORTHERLY FLOW BEHIND THE SYSTEM THURSDAY NIGHT WITH LIGHT PRECIP
IN THE FORM OF RAIN CHANGING TO SNOW FROM NORTH TO SOUTH.
SUBSTANTIAL MODEL DIFFERENCES BY NEXT WEEKEND WITH GFS SHOWING
STRONGER RIDGE AND DRYER WEATHER OVER ND ON SATURDAY WHILE ECMWF
HAS LESS AMPLIFIED PATTERN AND ANOTHER BATCH OF PRECIP MOVING IN
UNDER SOUTHWEST FLOW ALOFT.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 625 AM CDT MON APR 21 2014
MVFR STRATUS CONTINUES TO PUSH SOUTH ACROSS NORTHERN AND CENTRAL NORTH
DAKOTA AT THIS TIME...AND WILL CONTINUE TO DEVELOP SOUTH AND EAST
THROUGH MID-MORNING. IMPACTED LOCATIONS INCLUDE KISN-KMOT-KJMS
AND POSSIBLY KBIS. OTHERWISE VFR AT ALL TAF SITES THE REST OF THE
06Z FORECAST PERIOD.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...TM
SHORT TERM...NH
LONG TERM...JNS
AVIATION...NH
AREA FORECAST DISCUSSION
NWS BISMARCK ND
625 AM CDT MON APR 21 2014
.UPDATE...
ISSUED AT 625 AM CDT MON APR 21 2014
ONLY CHANGES TO FORECAST WERE TO POPULATE WITH LATEST HOURLY
OBSERVATIONS. TEMPS WERE RUNNING A LITTLE COLDER THAN FORECAST IN
A FEW LOCATIONS. OTHERWISE...LOW STRATUS CONTINUES TO SLOWLY PUSH
SOUTHWARD WHICH IS HANDLED WELL IN FORECAST.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 348 AM CDT MON APR 21 2014
NO MAJOR FORECAST HIGHLIGHTS IN THE SHORT TERM PERIOD.
CURRENTLY...QUASI-ZONAL FLOW ACROSS THE NORTHERN PLAINS WITH A
STRONG EMBEDDED S/WV TROUGH PUSHING EAST ALONG THE INTERNATIONAL
BORDER...NOW CENTERED NEAR TO EAST OF LAKE WINNIPEG. WRAP AROUND
MOISTURE IN THE FORM OF LOW LEVEL STRATUS SURGING SOUTH AND EAST
ACROSS MY NORTHERN COUNTIES THE PAST COUPLE OF HOURS. AT THIS TIME
DO NOT ANTICIPATE ANY PRECIPITATION ASSOCIATED WITH THE STRATUS.
WILL CONTINUE TO MONITOR.
LOW BKN-OVC CLOUDS WILL CONTINUE TO MOVE ACROSS NORTHWEST AND
NORTH CENTRAL NORTH DAKOTA NOW THROUGH 10Z...EVENTUALLY DEPICTED
BY BOTH THE RAP AND 00Z/06Z NAM TO PUSH AS FAR SOUTH AS BISMARCK
AND JAMESTOWN 10-14Z. AFTERWARDS...STRATUS SHOULD DISSIPATE/BURN
OFF BY THE EARLY AFTERNOON. THE MORNING CLOUDS COUPLED WITH CAA
THE PAST SEVERAL HOURS WILL RESULT IN HIGH TEMPERATURES TODAY IN
THE 50S ALONG TO NORTH AND EAST OF THE MISSOURI RIVER...60S SOUTH
AND WEST OF THE MISSOURI.
RETURN FLOW/WAA TONIGHT AS AN UPPER LEVEL RIDGE OF HIGH PRESSURE
AMPLIFIES ACROSS THE ROCKIES TODAY THEN PROPAGATES EAST INTO THE
HIGH PLAINS TONIGHT.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 348 AM CDT MON APR 21 2014
ACTIVE PERIOD EXPECTED WITH STRONG STORM SYSTEM APPROACHING THE
REGION TUESDAY NIGHT. LARGE SURFACE LOW INITIALLY CENTERED OVER
CENTRAL MONTANA 00Z WEDNESDAY TRANSITIONS TO DUAL SURFACE LOWS
OVER SOUTHEASTERN SASKATCHEWAN AND SOUTHEAST MONTANA BY 12Z WED AS
SHORTWAVE/90KT H250 JET STREAK ROTATE AROUND PARENT UPPER LOW.
BREEZY TO WINDY EAST/SOUTHEAST WINDS WILL OCCUR ALSO WITH TIGHT
SURFACE GRADIENT AND 850MB WINDS TO 45KTS LATE TUESDAY AND TUESDAY
NIGHT. SPC CONTINUES TO INCLUDE THE WESTERN HALF OF THE STATE IN
GENERAL THUNDERSTORM AREA WITH MODELS INDICATING LOW CAPE NUDGING
INTO THIS REGION ALONG WITH H7-H5 LAPSE RATES APPROACHING 8C/KM
TUESDAY NIGHT AHEAD OF THE COLD FRONT. MODELS CONTINUE TO SHOW
HIGHEST QPF ACROSS NORTH AND EAST AS DRY SLOT IS MORE OF A FACTOR
ACROSS WESTERN AND SOUTHERN AREAS. WEDNESDAY NIGHT INTO THURSDAY
THE CLOSED UPPER LOW AND ASSOCIATED SURFACE LOW MOVE ACROSS THE
NORTHERN PLAINS. MODEL DIFFERENCES INCREASE WITH THIS FEATURE WITH
THE GFS A LITTLE FASTER AND FARTHER SOUTH COMPARED TO ECMWF. BOTH
MODELS...HOWEVER...BRING SUB 0C H850 AIR ACROSS THE STATE IN
NORTHERLY FLOW BEHIND THE SYSTEM THURSDAY NIGHT WITH LIGHT PRECIP
IN THE FORM OF RAIN CHANGING TO SNOW FROM NORTH TO SOUTH.
SUBSTANTIAL MODEL DIFFERENCES BY NEXT WEEKEND WITH GFS SHOWING
STRONGER RIDGE AND DRYER WEATHER OVER ND ON SATURDAY WHILE ECMWF
HAS LESS AMPLIFIED PATTERN AND ANOTHER BATCH OF PRECIP MOVING IN
UNDER SOUTHWEST FLOW ALOFT.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 625 AM CDT MON APR 21 2014
MVFR STRATUS CONTINUES TO PUSH SOUTH ACROSS NORTHERN AND CENTRAL NORTH
DAKOTA AT THIS TIME...AND WILL CONTINUE TO DEVELOP SOUTH AND EAST
THROUGH MID-MORNING. IMPACTED LOCATIONS INCLUDE KISN-KMOT-KJMS
AND POSSIBLY KBIS. OTHERWISE VFR AT ALL TAF SITES THE REST OF THE
06Z FORECAST PERIOD.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...JNS
SHORT TERM...NH
LONG TERM...JNS
AVIATION...NH
AREA FORECAST DISCUSSION
NWS MEDFORD OR
847 AM PDT MON APR 21 2014
.SHORT TERM...A SERIES OF UPPER LEVEL TROUGHS IS EXPECTED TO MOVE
ACROSS THE REGION THIS WEEK BRINGING PRECIPITATION AND UNSETTLED
WEATHER. THIS MORNING, AN UPPER TROUGH IS LOCATED OFF THE PACNW COAST
AND A FRONT IS JUST OFFSHORE. AHEAD OF THE FRONT, SOUTHERLY
MOISTURE AND AREA OF VORTICITY WILL MOVE ACROSS THE CWA. THIS WILL
BRING SOME PRE-FRONTAL SHOWERS, MAINLY ALONG THE CASCADES AND
SISKIYOUS. THEN LATE IN THE AFTERNOON AND IN THE EVENING, EXPECT
THE FRONT TO BEGIN TO MOVE INLAND SPREADING STRATIFORM
PRECIPITATION ACROSS THE AREA THROUGH TONIGHT.
THE FORECAST REMAINS ON TRACK WITH THE FRONTAL SYSTEM MOVING INLAND
TONIGHT. AHEAD OF THE FRONT, HAVE INCREASED THE CHANCE FOR SHOWERS
ALONG THE CASCADES AND SISKIYOUS. ALSO HAVE ADDED A WIND
ADVISORY FOR THE SUMMER LAKE AREA FOR LATE THIS AFTERNOON AND THIS
EVENING. THE NAM, RAP AND GFS MODELS SHOW A 40 TO 50 KT SOUTHWEST JET
MOVING INTO THE AREA DURING THIS PERIOD. GUIDANCE ALSO INDICATES
GUSTS NEAR 45 MPH FOR THE SUMMER LAKE AREA LATE THIS AFTERNOON
INTO THIS EVENING. EXPECT THE MAIN AREA FOR GUSTY SOUTHWEST WINDS
WILL OCCUR FROM PAISLEY NORTH ALONG HIGHWAY 31 NEAR SUMMER LAKE.
OTHER AREAS THAT WILL SEE WINDS GUSTING TO 45 MPH WILL BE OVER THE
MOUNTAINS IN LAKE COUNTY.
&&
.AVIATION...BASED ON 21/12Z TAF CYCLE...A FRONT WILL BRING SOME RAIN
TO THE COAST LATE THIS AFTERNOON...AND PRECIPITATION WILL SPREAD
INLAND DURING THE EVENING. EXPECT CIGS TO LOWER TO MVFR
AT MOST WEST SIDE LOCATIONS DURING THIS TIME FRAME...AND LOWERED
FLIGHT CONDITIONS AND PRECIPITATION SHOULD REMAIN IN PLACE THROUGH
THE REMAINDER OF THE TAF PERIOD. EAST SIDE AND NORCAL LOCATIONS WILL
LIKELY REMAIN VFR THROUGH MONDAY...BUT GUSTY WINDS WILL DEVELOP IN
THE AFTERNOON. SOME AREAS OF MVFR CEILINGS AND VISIBILITIES COULD
DEVELOP OVER THE EAST SIDE LATE TONIGHT. FREEZING LEVELS WILL DROP
RAPIDLY BEHIND THE FRONT...REACHING DOWN TO 3000 TO 4000 FEET ABOVE
MSL BY 12 UTC TONIGHT. -BPN
&&
.MARINE...WEST SWELLS WILL CONTINUE TO GRADUALLY SUBSIDE THROUGH
TONIGHT AND EVENTUALLY STABILIZE AT AROUND 10 FEET ON MONDAY.
VARIOUS SWELL TRAINS WILL MOVE THROUGH THE AREA...KEEPING SEAS AT
AROUND 10 FEET THROUGH WEDNESDAY. A WEAK FRONT WILL PASS OVER THE
WATERS TODAY...PRODUCING LIGHT NORTH WINDS (15-20 KT) BEHIND IT
INTO MONDAY EVENING. A STRONGER FRONT IS EXPECTED WEDNESDAY AND
THIS WILL BRING SOLID SMALL CRAFT ADVISORY WINDS TO ALL WATERS
WITH GALES POSSIBLE OVER THE WATERS NORTH OF CAPE BLANCO. THE
MODELS ARE STARTING TO SHOW SOME CONSISTENCY WITH THIS
SOLUTION...THUS WILL PROBABLY NEED TO HOIST A GALE WATCH OVER THE
NEXT COUPLE OF MODEL CYCLES IF THIS TREND HOLDS. THURSDAY AND
FRIDAY LOOK QUIET...BUT ANOTHER MODERATELY STRONG FRONT IS
POSSIBLE THIS WEEKEND AND PERHAPS ANOTHER EARLY NEXT WEEK.
-WRIGHT/BPN
&&
.PREV DISCUSSION... /ISSUED 353 AM PDT MON APR 21 2014/
DISCUSSION...THE COLD FRONT IS MOVING INTO THE COASTAL WATERS
THIS MORNING. THIS FRONT IS ON TRACK TO BRING GUSTY WINDS TO THE
HIGHER TERRAIN OF THE WEST SIDE AND VERY GUSTY WINDS IN THE
KLAMATH AND GOOSE LAKE BASINS THIS AFTERNOON AND EVENING. SO FAR
WIND SPEEDS DON`T APPEAR TO BE STRONG ENOUGH FOR A WIND ADVISORY
BUT THIS BEARS WATCHING NONETHELESS. HOWEVER WINDS ARE FORECAST TO
BE VERY STRONG AT THE UPPER HALF OF MOUNT SHASTA (50+ MPH) AND ANY
HIKERS NEED TO TAKE THIS INTO CONSIDERATION.
SHORT TERM GUIDANCE DOES NOT BRING RAIN TO INLAND VALLEYS UNTIL
LATE AFTERNOON. THIS LOOKS REASONABLE AS UPPER LEVEL STEERING FLOW
IS ALMOST PARALLEL TO THE FRONT. ALSO WITH LACK OF STRONG
SOUTHEAST WINDS..WE SHOULD SEE MINIMUM DOWNSLOPING EFFECT AND THE
ROGUE VALLEY COULD SEE RAIN ALONG THE FRONT AS IT MOVES INLAND
THIS EVENING. THE FRONT MAY ALSO HAVE A FEW WAVES DEVELOP ALONG
THE FRONT WHICH SHOULD HELP SLOW THE EASTWARD PROGRESSION.
TONIGHT A SERIES OF STRONG WILL MOVE INLAND. THE UPPER LEVEL
TROUGH ASSOCIATED WITH THIS SYSTEM IS FAIRLY DEEP AND SHOWS A
NEGATIVELY TILTED PROFILE. THERE WILL ALSO BE A STRONG ONSHORE
FLOW WHICH WILL HELP ENHANCE PRECIPITATION ACROSS OUR FORECAST
AREA. BOTH THE GFS AND ECMWF ARE IN GOOD AGREEMENT ON RAINFALL
AMOUNTS AND TIMING. RAINFALL AMOUNTS UP TO HALF AN INCH OF RAIN IN
THE PARTS OF THE ROGUE AND UMPQUA VALLEYS ARE NOT UNREASONABLE FOR
TONIGHT TIME FRAME. PRECIPITATION IS MUCH LIGHTER EAST OF THE
CASCADES OVERNIGHT BUT THE KLAMATH BASIN IS EXPECTED TO PICK UP
TOWARD TUESDAY MORNING. SNOW LEVELS WILL REMAIN RATHER HIGH
TONIGHT AND THIS SHOULD NOT AFFECT TRAVEL ACROSS THE MAJOR PASSES.
COOLER NORTHWEST FLOW WILL BRING SNOW LEVELS DOWN ON TUESDAY.
CURRENT FORECAST CALLS FOR THE SNOW LEVELS TO LOWER TO AROUND 3500
TO 4000 FEET TUESDAY. THIS WILL DEFINITELY IMPACT TRAVELS ACROSS
THE CASCADES WITH A FEW INCHES OF SNOW POSSIBLE AND LESSER IMPACT
OVER THE SISKIYOU PASSES. WEAK SHORT WAVE RIDGING MOVES INTO THE
AREA TUESDAY AFTERNOON THROUGH TUESDAY NIGHT. PRECIPITATION CHANCE
DECREASES SOMEWHAT BUT THIS WILL BE SHORT LIVED AS A WARM FRONT
WILL BRING ANOTHER ROUND OF RAIN TO THE COAST WEDNESDAY. THIS WARM
FRONT WILL BRING VERY GUSTY WINDS TO THE COASTAL AREA WEDNESDAY
WITH RAIN SPREADING INLAND. SNOW LEVELS WILL RISE ON WEDNESDAY. THE
SECOND HALF OF THE WEEK COULD SEE SIGNIFICANT RAIN AT LEAST FOR
SOUTHWEST OREGON AND NORTHERN CALIFORNIA WITH HIGH LEVEL OF MOISTURE
TRANSPORT FROM THE PACIFIC. /FB
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...WIND ADVISORY FROM 3 PM THIS AFTERNOON TO 11 PM PDT THIS EVENING
FOR ORZ030-031.
CA...NONE.
PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 5 PM PDT WEDNESDAY
FOR PZZ350-356-370-376.
$$
CC
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
1037 AM CDT MON APR 21 2014
.UPDATE...
A NARROW BAND OF RAIN SHOWERS WITH ISOLATED THUNDER HAS DEVELOPED IN
SOUTH-CENTRAL WI. THIS IS ASSOCIATED WITH AN UPPER SHORTWAVE
APPROACHING FROM THE SW AND SURFACE TROUGH OVER THE STATE. RIGHT
ENTRANCE REGION OF UPPER JET OVER SE CANADA ALSO PROVIDING SOME
FORCING. HRRR AND RAP MODELS SLIDE THIS BAND TO THE SOUTHEAST
THROUGH THE EARLY AFTERNOON BEFORE ANOTHER BROKEN BAND COMES THROUGH
IN THE EVENING WITH THE SURFACE COLD FRONT.
NAM AND NMM INDICATE MU CAPE 600 TO 1600 J/KG ACROSS THE CWA SO
THUNDERSTORMS STILL A POSSIBILITY THROUGH THE DAY. ATMOSPHERE IS
VERY MOIST SO HEAVIER RAIN SHOWERS ARE POSSIBLE. 12Z GRB SOUNDING
STILL INDICATES PW VALUES 200 PERCENT OF NORMAL AT ABOUT 1 INCH.
MODELS SWEEP THE HIGH PW AXIS QUICKLY TO THE SOUTHEAST AND OUT OF
THE CWA LATE THIS EVENING. TEMPS STILL ON TRACK FOR LOWER 70S
TODAY. DRIER AND COLDER AIR WILL MOVE IN BEHIND THE FRONT ENDING
PRECIP CHANCES LATE IN THE EVENING.
&&
.AVIATION/18Z TAFS/...
SHOWERS WITH SCATTERED THUNDERSTORMS ARE EXPECTED TODAY. THOUGH
THERE IS CURRENTLY SOME ACTIVITY FROM THE WATERTOWN AREA SOUTHWEST
THROUGH MUCH OF DANE COUNTY...MANY LOCATIONS WILL LIKELY STAY DRY
UNTIL THE AFTERNOON HOURS. SOME LOWER CIGS/VSBYS ARE POSSIBLE
WITHIN HEAVIER SHOWERS/STORMS...BUT OTHERWISE VFR CONDITIONS WILL
PREVAIL THROUGH TUESDAY.
RAIN CHANCES WILL WIND DOWN FROM NORTHWEST TO SOUTHEAST LATER
AFTERNOON INTO THE EVENING...WITH DRY WEATHER THEN EXPECTED
OVERNIGHT AND TUESDAY.
&&
.PREV DISCUSSION... /ISSUED 325 AM CDT MON APR 21 2014/
TODAY AND TONIGHT...FORECAST CONFIDENCE - MEDIUM.
FOCUS OF THIS FORECAST ON PRECIP THREAT TODAY. WATER VAPOR PLUME OF
DEEPER MID-UPPER LEVEL MOISTURE HAS BEEN SPREADING INTO WISCONSIN
OVERNIGHT. COLUMN PRECIPITABLE WATER VALUES WILL INCREASE TO
BETWEEN 1 AND 1.25 INCHES TODAY OVER SRN WI...AHEAD OF SHARPENING
MID-LEVEL TROUGH. PWAT VALUES AT THIS RANGE FOR MID-APRIL ARE ABOUT
150-200 PERCENT OF NORMAL AND ABOVE THE 75TH PERCENTILE...
APPROACHING 2 STANDARD DEVIATIONS AT KGRB. INITIAL SURGE OF MOISTURE
HELPING TO TRIGGER SCATTERED -SHRA EARLY THIS MRNG OVER SRN WI WITH
MORE -SHRA INCREASING UPSTREAM OVER SOUTHEAST IA INTO WRN IL. WL
KEEP SCT OR CHC POPS OVER MOST OF THE AREA THROUGH THE MID-MORNING
WITH LIKELY WORDING CONTINUING IN THE FAR WEST CLOSER TO BETTER
SYNOPTIC SCALE LIFT.
LATER THIS MORNING THROUGH THE AFTN...PHASING OF STRONGER MID-LEVEL
SHORT WAVE CURRENTLY IN VICINITY OF ND/MN BORDER INTO SRN CANADA
WITH WEAKER WAVE MOVING THROUGH SRN STREAM. LAYER Q-VECTOR
CONVERGENCE INCREASES DURING THIS PERIOD BUT VALUES REMAIN LESS THAN
10 UNITS. CONSIDERING THAT RIGHT ENTRANCE REGION OF UPPER JET
BRUSHES PORTIONS OF SRN WI LATER TODAY...RATHER SURPRISED Q-VECTOR
CONVERGENCE NOT A LITTLE STRONGER. NEVER THE LESS...WITH DEEP
COLUMN MOISTURE IN PLACE...THINK SHOWERS AND SCT T WILL BECOME MORE
WIDESPREAD LATER THIS MRNG AND AFTN...SO INCREASED POPS TO
CATEGORICAL FOR SEVERAL HOURS. MUCAPE INCREASES TO 500 TO 1000 J/KG
BUT BULK SHEAR REMAINS LOW. NOT IMPOSSIBLE STRONGER T MAY PRODUCE
SMALL HAIL LATER TODAY. ALSO...CORFIDI VECTORS REMAIN BETWEEN 5 TO
15 KNOTS DURING PEAK FORCING. WARM CLOUD DEPTH REMAINS LESS THAN 7K
FEET...HOWEVER SOME LOCATIONS MAY RECEIVE SEVERAL BOUTS OF MODERATE
SHRA/T THAT MAY RESULT IN ONE HALF INCH TO ONE INCH OF RAINFALL
CAUSING LOCALIZED MINOR STREET FLOODING.
SHARPENING MID-LEVEL TROUGH EXITS AREA FAIRLY QUICKLY DURING THE
LATE AFTN AND EARLY EVENING AS DRIER...COLDER AIR SWEEPS IN. WL
CARRY CHANCE POPS IN THE EARLY EVENING IN THE SOUTHEAST FOLLOWED BY
CLEARING SKIES. BOUNDARY LAYER MIXING AND INFLUX OF DRIER AIR WILL
PREVENT FOG FORMATION.
TUESDAY CONFIDENCE...MEDIUM
UPPER TROUGH SHIFTS TO THE EAST WITH COLD ADVECTION CONTINUING.
LOW LEVEL COLD POOL LINGERS FOR THE DAY WITH 850 TEMPS A DEGREE OR
SO EITHER SIDE OF 0C. 925 TEMPS CONSIDERABLY COLDER AT ONLY 4-7C.
THIS WILL LIKELY YIELD HIGHS OF ONLY IN THE 50S AT INLAND AREAS
OUTSIDE OF THE LAKE INFLUENCE. MANY LAKESHORE LOCATIONS LIKELY TO
STAY IN THE 40S. LOW LEVEL RH PROGS AS WELL AS MOS SHOWING A MUCH
MORE GLANCING SHOT OF LOW LEVEL RH..MAINLY IN THE FAR EAST EARLY
ON. HOWEVER MOS AND BUFKIT ARE REALLY SHOWING A VERY PARCHED LOOK
SO LOOKS LIKE PLENTY OF SUNSHINE ON TAP.
WEDNESDAY - CONFIDENCE...MEDIUM
HIGH PRESSURE RIDGE SHIFTS EAST WITH SE LOW LEVEL FLOW. MID LEVEL
RIDGE AXIS APPROACHES. LOW LEVEL WAA STARTS TO INCREASE. HOWEVER
850 JET CORE WELL WEST OF THE AREA THROUGH 18Z WITH DRY AIRMASS
STILL IN PLACE. BUFKIT SOUNDINGS REVEAL THE VAST AMOUNT OF LOW
LEVEL DRY AIR TO OVERCOME EAST OF THE LLJ AXIS. THE NAM IS MUCH
MORE PRONOUNCED IN THIS REGARD ESP IN THE ERN CWA...WITH THE GFS
STILL SHOWING DRY AIR THOUGH NOT AS DEEP. MODELS ARE IN SYNC WITH
KEEPING PRECIP LARGELY WEST OF CWA THROUGH 18Z...THEN SOME
DIVERGENCE OCCURS IN THE AFTERNOON AS THE GEM/NAM ARE SLUGGISH TO
EXPAND PRECIP INTO THE EAST...WHICH HAS MERIT GIVEN THE EXTENT OF
DRY AIR ON THE PROGGD SOUNDINGS...WHILE THE GFS/ECMWF BRING QPF
ALL THE WAY INTO ERN WI. WILL CONTINUE THE IDEA OF HAVING HIGHEST
POPS IN THE WEST...IN BETTER PROXIMITY TO LOW LEVEL JET AXIS.
WEDNESDAY NIGHT - CONFIDENCE...MEDIUM
LLJ RAMPS UP AND TRANSLATES EAST INTO WI. GREATEST MOISTURE
INFLUX ASSOCIATED WITH LLJ AND OVERALL PROGGD POSITION OF LLJ
DYNAMICS FAVORS PORTIONS OF WRN AND NRN WI FOR THE BETTER/MORE
ORGANIZED CONVECTIVE POTENTIAL.
THURSDAY AND THURSDAY NIGHT - CONFIDENCE...MEDIUM
POTENT SHORTWAVE APPROACHES FROM THE PLAINS WITH BEST DCVA FROM
LATE AFTN INTO THE ERLY EVE HOURS. SOME DISAGREEMENT ON POSITIONING
OF SFC LOW CENTER WITH THE GFS MORE OF BLEND OF THE SRN ECMWF AND
MORE NW GEM SOLUTIONS. CWASP VALUES ARE NOW JUST SHOWING 50S WITH
THE BETTER VALUES FURTHER SOUTH OF THE STATE WHICH IS ALSO
HIGHLIGHTED BY THE CIPS ANALOG GUIDANCE. BUFKIT SOUNDINGS ARE ALSO
NOT SHOWING A VAST AMOUNT OF CAPE TO WORK WITH. SO WHILE A DECENT
COVERAGE OF SHRA/TSRA EXPECTED...CONFIDENCE IN ORGANIZED SVR IS
RATHER LOW AT THE MOMENT.
FRIDAY - CONFIDENCE...MEDIUM
COLD FRONT WILL HAVE SHIFTED OFF TO THE EAST BUT LOW PRESSURE
SLOW TO DEPART THE REGION. SO EXPECTING A SHOWERY REGIME TO
LINGER. SEVERAL SPOKES OF VORTICITY LIKELY TO BE ENHANCING LIFT IN
ADDITION TO THE SURFACE/850 TROUGH AXES COMING INTO PLAY.
SATURDAY AND SUNDAY - CONFIDENCE...LOW
SUBSTANTIAL MODEL DIFFERENCES WITH THE GFS SHOWING A MORE
PROLONGED INFLUENCE OF THE ERN UPPER TROUGH. MEANWHILE THE ECMWF
IS MORE PROGRESSIVE WITH THAT FEATURE WITH A RENEWED TROUGH MORE
AGGRESSIVELY ADVANCING INTO THE PLAINS AND SETTING UP AN ACTIVE
BAROCLINIC ZONE EVENT FROM IOWA INTO ILLINOIS WITH SRN WI ON THE
NRN FRINGE OF PRECIP. ALLBLEND POPS TO HANDLE THIS FOR NOW WITH
RAIN CHANCES IN THE EXTREME SW CWA SATURDAY AND EXPANDING CWA
WIDE FOR SUNDAY.
AVIATION/12Z TAFS/...MAINLY VFR CONDITIONS EXPECTED FOR BULK OF
THIS FORECAST CYCLE. HOWEVER LIKELY TO BE SEVERAL ROUNDS OF PRECIP
AFFECTING TAF SITES. BEST CHANCE LATER THIS MRNG THROUGH MID-LATE
AFTN WHEN SCT T WILL BE IN THE VICINITY. BRIEF HEAVY RAINFALL MAY
ACCOMPANY SHRA/T AS WELL WITH LIKELY MVFR CIGS/VSBYS. PATCHY LIGHT
FOG MAY AFFECT KMSN EARLY THIS MRNG AS WELL.
MARINE...LIGHT AND VARIABLE WINDS WILL BECOME MORE SOUTH TO
SOUTHEAST THIS MORNING AND THEN VEER TO THE SOUTHWEST AHEAD OF
APPROACHING COLD FRONT THIS AFTERNOON. COLD FRONT EXPECTED TO SWEEP
ACROSS SOUTHWEST LAKE MI LATE AFTN AND EARLY EVE CAUSING WINDS TO
CONTINUE VEERING TO THE NORTHWEST. ENOUGH OF A SURGE OF COLD AIR
BEHIND FRONT TO CAUSE WIND GUSTS TO 25 KNOTS OVER THE NEARSHORE
WATERS AS PRESSURE GRADIENT TIGHTENS. WL POST SMALL CRAFT ADVY FOR
TNGT THRU TUE MRNG.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...SMALL CRAFT ADVISORY FROM 7 PM THIS EVENING TO 1 PM CDT TUESDAY
FOR LMZ643>646.
&&
$$
UPDATE...SM/DDV
TODAY/TONIGHT AND AVIATION/MARINE...MBK
TUESDAY THROUGH SUNDAY...COLLAR
AREA FORECAST DISCUSSION
NWS PUEBLO CO
328 PM MDT MON APR 21 2014
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 328 PM MDT MON APR 21 2014
...INCREASING WINDS FOR TUESDAY...
UPPER RIDGE AXIS HAS BEEN SHIFTING EASTWARD ACROSS CO THIS AFTERNOON
WITH WEAK PV ANOMALY EXITING THE SOUTHEAST PLAINS. SFC DEW POINTS
HAVE DROPPED OFF INTO THE 20S ACROSS MOST OF THE AREA...WITH SOME
LOWER TO MID 30S ACROSS THE SOUTHERN PORTIONS OF THE SOUTHEAST
PLAINS AND SOUTHERN I-25 CORRIDOR. AFTERNOON HEATING HAS TRIGGERED
ANOTHER ROUND OF SHOWERS AND THUNDERSTORMS ACROSS THE
MOUNTAINS...BUT WITH LACK OF FORCING COVERAGE HAS BEEN PRETTY SPARSE
AND LACK OF MOISTURE HAS LIMITED UPDRAFT STRENGTH. HRRR HAS BEEN
TRENDING DRIER WITH EACH RUN...SO HAVE DECREASED POPS FOR THE
EVENING HOURS...AND CONVECTION SHOULD DIMINISH QUICKLY THIS EVENING
ONCE THE SUN GOES DOWN.
SOUTHWEST FLOW ALOFT INCREASES FOR TUESDAY...WHICH SHOULD INCREASE
WINDS ACROSS THE FORECAST AREA BY AFTERNOON. MOISTURE BEGINS TO
INCREASE ACROSS THE SOUTHWEST MOUNTAINS EARLY TUESDAY MORNING...WITH
SOME ISOLATED SHOWERS SPREADING IN. WITH AFTERNOON
HEATING...ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS WILL
DEVELOP OVER THE MOUNTAINS DURING THE AFTERNOON...THEN SPREAD OFF
INTO THE ADJACENT PLAINS DURING THE LATE AFTERNOON. ONE CONCERN FOR
TOMORROW IS THE POTENTIAL FOR NEAR CRITICAL FIRE WEATHER CONDITIONS
ALONG PORTIONS OF THE I-25 CORRIDOR. GFS IS DRIER WITH SFC DEW
POINTS (UPPER 20S)...WHILE NAM ACTUALLY INCREASES THEM IN THE
AFTERNOON (30S TO AROUND 40) AS CLOUDS INCREASE AND -SHRA/VIRGA
DRIFT OFF THE MOUNTAINS. LATEST 4KM WRF ALSO SHOWS THIS MOISTENING
TREND DURING THE AFTERNOON. FARTHER EAST...SOUTHERLY FLOW KEEPS MID-
UPPER 30S ACROSS THE FAR EAST PLAINS WHICH RESULTS IN AFTERNOON
HUMIDITIES IN THE 18-25% RANGE...TOO HIGH FOR FIRE WEATHER
HIGHLIGHTS. QUITE A BIT OF HUERFANO COUNTY HAD SOME GOOD RAIN FROM
THE SYSTEM OVER THE WEEKEND...SO THE MOST LIKE SPOTS FOR MARGINAL
CRITICAL FIRE WEATHER CONDITIONS TO DEVELOP WOULD BE PUEBLO
COUNTY...SOUTHERN EL PASO...AND WESTERN LAS ANIMAS COUNTIES. LOCAL
WRF IS SLOW TO INCREASE WINDS ACROSS PUEBLO COUNTY UNTIL LATE
AFTERNOON WHICH MAY LIMIT THE DURATION TO LESS THAN THE 3 HR
REQUIRED MINIMUM. WITH ALL THESE MARGINAL CRITERIA...DECIDED NOT TO
HOIST ANY FIRE WEATHER HIGHLIGHTS...BUT THIS WILL BE MONITORED
CLOSELY AS MORE HIGH RES MODELS BEGIN TO RESOLVE THESE FINER
DETAILS.
OTHERWISE...ANOTHER ROUND OF ISOLATED TO SCATTERED AFTERNOON SHOWERS
AND THUNDERSTORMS WILL DEVELOP. THESE WILL BE PRETTY HIGH BASED AND
MORE LIKELY TO PRODUCE GUSTY WINDS AND LIGHTNING AND ONLY SOME BRIEF
LIGHT TO MODERATE RAINFALL AMOUNTS IN SPOTTY AREAS. A MARGINALLY
STRONG THUNDERSTORM OR TWO WILL BE POSSIBLE ALONG A DIFFUSE DRY LINE
ACROSS THE FAR SOUTHEAST PLAINS DURING THE AFTERNOON...BUT CAPES
WILL ONLY BE RUNNING AROUND 500 J/KG OR LESS...WITH GUSTY WINDS THE
PRIMARY STORM THREAT. -KT
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 328 PM MDT MON APR 21 2014
RELATIVELY ACTIVE LONGER TERM PATTERN SETTING UP OVER THE
FORECAST DISTRICT...ESPECIALLY FROM THE WEEKEND INTO EARLY NEXT
WEEK. PRIMARY LONGER TERM METEOROLOGICAL CHALLENGES INCLUDE BUT
ARE NOT LIMITED TO POPS...TEMPERATURES...ELEVATED FIRE WEATHER
CONCERNS AT TIMES AND THE POTENTIAL FOR SOME STRONG TO POTENTIALLY
SEVERE THUNDERSTORMS OVER/NEAR EASTERN SECTIONS AT TIMES.
RECENT LONGER TERM FORECAST MODEL SOUNDINGS AND COMPUTER MODEL
SIMULATIONS INDICATE THAT INITIAL UPPER DISTURBANCE WILL MOVE
PRIMARILY TO THE NORTH OF THE CWFA FROM WEDNESDAY INTO WEDNESDAY
NIGHT ALLOWING FOR SOME SHOWER ACTIVITY OVER MAINLY NORTHERN
SECTIONS AS WELL AS INCREASED DRY SOUTHWESTERLY SURFACE FLOW OVER
EASTERN PORTIONS OF THE FORECAST DISTRICT...THEREFORE WILL ALLOW
THE FIRE WEATHER WATCH TO REMAIN IN EFFECT FROM WEDNESDAY
AFTERNOON INTO WEDNESDAY EVENING FOR THE INTERSTATE 25 CORRIDOR AS
WELL AS OVER ALL OF THE SOUTHEASTERN COLORADO PLAINS. IN
ADDITION...A SURFACE DRY LINE IS EXPECTED TO SET-UP NEAR THE
COLORADO/KANSAS BORDER WEDNESDAY...WITH THE SPC DAY 3 CONVECTIVE
OUTLOOK PAINTING A SLIGHT RISK OF SEVERE THUNDERSTORMS ON
WEDNESDAY JUST EAST OF THE COLORADO/KANSAS BORDER. WFO PUEBLO
WILL MONITOR CLOSELY.
THEN BASICALLY DRY ZONAL TO SOUTHWESTERLY UPPER FLOW IS EXPECTED
TO DEVELOP OVER SOUTHERN COLORADO FROM LATER WEDNESDAY NIGHT INTO
SATURDAY MORNING IN ADVANCE OF NEXT APPROACHING SYSTEM. AT THIS
TIME WILL DEPICT GENERALLY DRY CONDITIONS DURING THIS TIME-FRAME
IN COMBINATION WITH ELEVATED FIRE WEATHER CONCERNS DURING THE
AFTERNOON AND EVENING HOURS OVER PORTIONS OF THE SAN LUIS VALLEY
AND SOUTHEASTERN COLORADO PLAINS.
NEXT POTENTIALLY SIGNIFICANT SYSTEM IS PROJECTED TO BEGIN IMPACTING
THE FORECAST DISTRICT FROM LATER SATURDAY INTO EARLY NEXT WEEK.
COMPUTER SIMULATIONS HAVE VARYING FORECAST TRACKS WITH THIS SYSTEM
WITH GFS FURTHEST SOUTH AND ECMWF AND DGEX FURTHER NORTH THROUGH
18Z NEXT MONDAY. WFO PUEBLO WILL CONTINUE TO CLOSELY MONITOR THE
TRACK AND STRENGTH OF THIS POTENTIAL SYSTEM AS IT NEARS THE
FORECAST DISTRICT BY THIS WEEKEND.
FINALLY...ABOVE SEASONAL LATE APRIL TEMPERATURES ARE PROJECTED TO
CONTINUE OVER THE MAJORITY OF THE FORECAST DISTRICT FROM TUESDAY
EVENING INTO SUNDAY MORNING WITH BELOW SEASONAL TEMPERATURES THEN
ANTICIPATED FROM LATER SUNDAY INTO EARLY NEXT WEEK.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 328 PM MDT MON APR 21 2014
VFR CONDITIONS EXPECTED AT THE TAF SITES THROUGH THE
NEXT 24 HOURS. ISOLATED -SHRA/-TSRA WILL CONTINUE ACROSS THE
MOUNTAINS...WITH A FEW WEAK CELLS MOVING INTO THE ADJACENT LOWER
ELEVATIONS THROUGH THE EVENING HOURS. PROBABILITIES OF ONE OF THESE
IMPACTING THE TAF SITES LOOKS TOO SMALL AT THIS POINT TO WARRANT
INCLUSION IN THE TAFS...THOUGH WILL HAVE TO WATCH FOR GUSTY WINDS
FROM OUTFLOW BOUNDARIES AS THEY COME OFF THE MOUNTAINS. INCREASING
SOUTH TO SOUTHWEST WINDS EXPECTED FOR TUESDAY...WHICH WILL PROBABLY
START AT THE KCOS AND KALS TAF SITES DURING THE LATE MORNING TO
AROUND THE NOON HOUR. GUSTY WINDS WILL TAKE A LITTLE LONGER TO SET
IN AT KPUB. GUSTS UP TO 30 KTS WILL BE POSSIBLE DURING THE
AFTERNOON. ANOTHER ROUND OF ISOLATED TO SCATTERED SHOWERS AND
THUNDERSTORMS WILL DEVELOP OVER THE MOUNTAINS DURING THE
AFTERNOON...WHICH WILL SPREAD INTO THE SOUTHEAST PLAINS DURING THE
LATE AFTERNOON. THESE WILL BE HIGH BASED AND MORE LIKELY TO PRODUCE
GUSTY ERRATIC WINDS AND LIGHTNING...ALONG WITH SOME BRIEF LIGHT TO
MODERATE RAINFALL. -KT
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
FIRE WEATHER WATCH FROM WEDNESDAY AFTERNOON THROUGH WEDNESDAY
EVENING FOR COZ226>237.
&&
$$
AREA FORECAST DISCUSSION
NWS DES MOINES IA
105 PM CDT MON APR 21 2014
.SHORT TERM /TODAY/...
ISSUED AT 343 AM CDT MON APR 21 2014
STUBBORN COLD FRONT WILL FINALLY SWING THROUGH THE STATE
TODAY AND BRING SCATTERED SHOWERS AND A FEW THUNDERSTORMS TO THE
FORECAST AREA DURING MUCH OF THE MORNING. FRONT LOOKS TO CREEP INTO
NORTHWEST PORTIONS OF THE FORECAST AREA BY AROUND 14-15Z AND
CONTINUE TO PUSH SOUTHEAST AND CLEAR MUCH OF THE FORECAST AREA BY
AROUND 00Z TUESDAY OR SLIGHTLY SOONER. LEANED TOWARD THE SLOWER
SREF/GFS/ECMWF WRT TO WINDS AND TEMPERATURES TODAY. 21.05Z HRRR IS A
LITTLE TOO FAST WITH THE PRECIP MOVING EAST AND THE 21.03Z HOPWRF IS
LIGHTER ON THE COVERAGE. REGARDLESS...UTILIZED A BLEND OF THE TWO
FOR POPS/WX TRENDS THROUGH MIDDAY TODAY...THEN THE 21.03Z
SREF/21.00Z HIRES-ARW/NMM FOR TRENDS THIS AFTERNOON.
SURFACE LOW LOCATED OVER NORTHWEST IOWA/SOUTHWEST MINNESOTA WITH
COLD FRONT EXTENDING SOUTHWEST INTO NEBRASKA. WEAK AND BROAD LARGE
SCALE FORCING AHEAD THIS COLD FRONT AS WELL AS ISENTROPIC LIFT WILL
CONTINUE TO FEED MOISTURE INTO THE FORECAST AREA THIS MORNING.
INSTABILITY NOT IMPRESSIVE TODAY BUT ENOUGH AVAILABLE TO KEEP
MENTION OF THUNDER. HAVE BULK OF THE HIGHER POPS OVER WESTERN AND
NORTHERN IOWA THROUGH 12-14Z BEFORE SHIFTING FURTHER SOUTHEAST LATE
THIS MORNING. BELIEVE MUCH OF THE PRECIP WILL QUICKLY DISSIPATE PAST
18-20Z OR BE CONFINED TO THE SOUTHEAST CORNER OF THE FORECAST AREA.
HAVE NON-DIURNAL TEMPERATURE TREND MENTIONED ACROSS THE NORTH AS
SHOULD SEE THE CAA DEVELOP LATE THIS MORNING AND INCREASE THROUGH
THE AFTERNOON. 850MB TEMPS DROP TO +4C TO +6C BY 18Z IN THE NORTH.
GUSTY NORTH TO NORTHWEST WINDS BEHIND THE FRONT WITH WINDS ATOP THE
MIXED LAYER INCREASING TO AROUND 25 TO 30 KNOTS. MUCH DRIER AIR MASS
FILTERS INTO THE STATE AS WELL WITH SURFACE DEW POINTS DROPPING INTO
UPPER 30S AND LOWER 40S OVER THE NORTHWEST. RH VALUES DECREASE TO
NEAR 25 PERCENT ACROSS A SMALL WESTERN PORTION OF FORECAST AREA.
THOUGH AN INCREASED FIRE WEATHER DANGER TODAY...HELD OFF ON RED FLAG
WARNING DUE TO CRITERIA NOT BEING MET WIDESPREAD.
.LONG TERM /TONIGHT THROUGH SATURDAY/...
ISSUED AT 343 AM CDT MON APR 21 2014
EARLY IN THE PERIOD...FEW CONCERNS. SYSTEM ON THE WAY OUT BY 00Z
TONIGHT WITH SECONDARY COLD FRONT NOW OVER NORTHERN MN DROPPING
SOUTHEAST ACROSS THE REGION TONIGHT...BRINGING DRIER AND COOLER AIR
INTO THE REGION BY MORNING. DESPITE WARM TEMPS THE PAST FEW DAYS...
MORNING LOWS TONIGHT WILL BE MUCH COOLER WITH MID 30S NORTH TO MID
40S SOUTH. TUESDAY LOOKS LIKE A NICE DAY WITH GENERALLY SUNNY SKIES
AND A FEW FAIR WX CUMULUS DURING THE MID AFTERNOON AS HIGH PRESSURE
DROPS SOUTHEAST THROUGH THE DAY...KEEPING WINDS LIGHT. LITTLE MIXING
TO PROMOTE MUCH WARMING OTHER THAN SUNSHINE...SO WILL STICK WITH
HIGHS IN THE UPPER 50S NORTHEAST AND MID 60S ACROSS THE WEST. MODELS
DIFFER SLIGHTLY ON TIMING OF UPSTREAM WAVE AND EXPECTED WARM AIR
ADVECTION/CLOUDS AND APPROACHING SHOWERS FOR WED. OVERALL...INCREASE
IN CLOUDS EXPECTED LATE DAY WEST TUESDAY WITH SHOWERS NEARING THE
WESTERN BORDER BY 12Z. THOUGH THUNDER MORE LIKELY ACROSS THE HIGH
PLAINS AND NE...DRY AIR OVER IOWA WILL COOL AND DIMINISH INSTABILITY
WHEN INITIAL PUSH OF MOISTURE ARRIVES. MODELS SHOW LITTLE
INSTABILITY UNTIL AFTERNOON WED AND THAT AGAIN IS LESS THAN
YESTERDAYS SOLUTIONS. THUS...HAVE TRIMMED AREAL COVERAGE OF THUNDER
TO ISO WEST IN THE MORNING AND ISO EAST/SCT FAR WEST IN THE PM HOURS
WEDNESDAY WITH THE FIRST REAL SURGE OF THETAE ADVECTION. AS THE
SYSTEM CROSSES THE REGION...CONFIDENCE IN EVOLUTION OF SYSTEM HAS
LESSENED SLIGHTLY. MODELS CONTINUE TO HAVE GENERAL TRENDS SIMILAR...
BUT DETAILS DIFFER. OVERALL THE BETTER INSTABILITY WILL REMAIN WEST
OF THE AREA UNTIL NEARER 00Z THUR...THEN WEAKEN OVERNIGHT PRIOR TO
INCREASING AGAIN FROM LATE MORNING THUR THROUGH 00Z FRI. STILL SOME
CONCERNS ABOUT OVERNIGHT CONVECTION ACROSS SOUTH/CENTRAL SECTIONS
WED NIGHT AS SOME BULK SHEAR COULD AID SVR POTENTIAL. BOTH THE
00Z GFS AND THE 12Z/NEW 00Z EURO NOW SUGGEST THAT THE LOW WILL
TRACK NORTHEAST ACROSS IA NEARLY EXITING OUR FORECAST AREA BY
18Z THUR...KEEPING THE BEST INSTABILITY AND SVR POTENTIAL EAST OF
THE AREA BY THURSDAY AFTERNOON. FOR NOW...WILL CONTINUE TO MONITOR
POTENTIAL BUT OVERALL CHANCES WOULD REMAIN CONDITIONAL ON ANY
BETTER ALIGNMENT OF FORCING AND STRONGER INSTABILITY THURSDAY.
BEYOND THUR AFTERNOON...MORE UNCERTAINTY IS ARISING IN THE
REMAINDER OF THE FORECAST. MODELS HANDLING THE DEPARTURE OF THE
SYSTEM WITH DIFFERING SPEED THUR NIGHT AND FRIDAY DUE TO A
SECONDARY H500 SYSTEM OVER CENTRAL CANADA POTENTIALLY PHASING WITH
THE DEPARTING H500 LOW. BOTH THE GEM/EURO TAKE THE FIRST SYSTEM
EAST QUICKLY ENOUGH TO PREVENT MUCH PHASING WHILE THE GFS HOLDS ON
TO A TROUGH EXTENDING WEST INTO MN. THIS RESULTS IN A FARTHER WEST
RIDGE AXIS OVER CANADA THAT DROPS SOUTH INTO THE NORTHERN PLAINS
AND DRIVES THE JET STREAM FARTHER SOUTH...DIRECTLY NEXT WEEKENDS
STORM SOUTH OF IOWA. THE GEM/EURO SHOW ONLY A SLIGHT DELAY IN
TIMING AND STILL BRING RAIN BACK INTO THE AREA FOR THE WEEKEND.
FOR NOW THE GFS SHOWS TOO DRASTIC A CHANGE FOR SUCH A SMALL H500
FEATURE. DUE TO UNCERTAINTY...WILL CUT BACK ON POP CHANCE AT ONSET
OF PRECIP EVENT NEXT SATURDAY BUT WILL STILL KEEP POP INCREASING
WITH TIME THROUGH SUNDAY. TEMPS WILL HAVE EVEN GREATER UNCERTAINTY
NOW...AS TIED TO CHANGES IN EVOLUTION AND TRACK OF WEEKEND UPPER
AIR PATTERN AND STORM TRACK. NEWEST 21/00Z EURO STILL KEEPS TREND
OF WET WEATHER NEXT WEEKEND...WHILE THE GFS REMAINS DRY. OVERALL
THE EURO TENDS TO PERFORM MORE CONSISTENTLY AFTER FCST 120 HOURS
SO WILL LEAN TOWARD GEM/EURO SOLUTIONS OF WETTER WEATHER SAT/SUN.
AS MENTIONED IN PREVIOUS NIGHTS AFDS...THERE IS A CONSISTENT
SIGNAL OF ENERGY STRETCHING FROM THE NORTH CENTRAL PACIFIC EAST TO
THE PLAINS...WHICH WOULD FAVOR INCLEMENT WEATHER HERE.
&&
.AVIATION...21/18Z
ISSUED AT 1257 PM CDT MON APR 21 2014
COLD FRONT ACROSS CENTRAL IOWA WILL EXIT INTO ILLINOIS AND
MISSOURI BY LATE THIS AFTERNOON. STRONG NORTHWEST SURFACE WINDS
ARE EXPECTED ON THE BACKSIDE OF THE FRONT THIS AFTERNOON BEFORE
DIMINISHING SOME THIS EVENING AS MIXING DECREASES. SCATTERED
SHOWERS AND THUNDERSTORMS IN THE VICINITY OF KOTM WILL DEPART WITH
THE FRONT AS WELL. SCATTERED AREAS OF MVFR CEILINGS WILL GIVE WAY
TO WIDESPREAD VFR CONDITIIONS BY THIS EVENING ACROSS ALL OF
CENTRAL IOWA WITH THESE CONDITIONS PERSISTING FOR THE REMAINDER OF
THE FORECAST PERIOD.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...PODRAZIK
LONG TERM...REV
AVIATION...COGIL
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1205 PM CDT Mon Apr 21 2014
...UPDATE TO AVIATION...
.SYNOPSIS...
ISSUED AT 950 AM CDT MON APR 21 2014
Water vapor imagery and 12Z upper air analysis indicate an upper
level shortwave trough transitioning eastward across the Central
Plains. Meanwhile, upper level ridging is shifting eastward across
the Intermountain West. Near the surface, a weak cold front extends
from southeastern Colorado northeast across west central Kansas into
southeastern Nebraska. High pressure is building behind the front
across the Colorado Rockies.
&&
.SHORT TERM...(Today and tonight)
ISSUED AT 317 AM CDT MON APR 21 2014
The main shortwave trough is depicted by the models to move into
eastern Kansas this morning. The RUC model has picked up on the MCV
over central Kansas and moves it southward into northwest Oklahoma
today in the northwesterly flow on the backside of the trough. Model
soundings show instability around 600-800 j/kg of CAPE as a mid
level cold pool moves southeast across western Kansas today. Given
the forcing with the MCV and a nearly uncapped sounding profile this
afternoon over south central Kansas, will add some slight chance
pops for showers and isolated thunder to the forecast.
Things will quiet down fairly quickly late this afternoon and early
evening as a ridge of surface high pressure moves east through the
High Plains. Winds will become light and variable in the evening and
gradually swing around to the southeast and south. Overnight lows
will be the coolest over central Kansas where low to mid 40s are
expected. Lows will drop into the upper 40s to around 50 along the
Colorado border where increasing southerly winds will help keep
temperatures up a few degrees more.
.LONG TERM...(Tuesday through Sunday)
ISSUED AT 414 AM CDT MON APR 21 2014
An upper ridge will be transitioning eastward across the Great
Plains on Tuesday. Surface pressure falls along the lee of the
Rockies and the retreating surface high pressure across the Missouri
valley will create a moisture transport zone over the central High
Plains, effectively causing an increasing in surface and 850 mb dew
points across western and central Kansas. Afternoon heating across
the higher terrain around the Palmer Divide will allow thunderstorms
to form and be steered eastward into this moisture and instability
axis. Some thunderstorms could move into western Kansas through the
evening hours most likely around Syracuse. With a lack of dynamics,
convection should be mainly diurnally driven, and as a result dry
weather is likely through the overnight Tuesday into Wednesday
morning with mild lows. An upper wave will be approaching the
region Wednesday with several impacts. A decent surface pressure
gradient will be in place as much drier air mixes out eastward
though the morning and afternoon. The overall momentum transfer will
probably be negatively influenced by mid level cloud decks indicated
on model soundings and may even prevent a high wind event given 0-1
km mean winds on the order of 35-40 knots. Additionally a set up for
severe storms will exist along and ahead of the dryline as the
atmosphere destabilizes through the morning. Potential for rotating
supercells exist with NAM model suggesting around 2-3 m2/s2 EHI(3km)
with up to round 2000 J/kg of surface based CAPE ahead of the
dryline feature. Good subsidence should follow in behind this
dryline overnight into Thursday morning. Dry and warm conditions
will likely follow into Friday as the next flat upper ridge settle
across the region. Additional thunderstorm chances are in the
forecast later in the weekend and early nextweek associated with
yet another west coast jet carving a trough into the southern
Rockies by the GFS and ECMWF.
&&
.AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon)
ISSUED AT 1203 PM CDT MON APR 21 2014
VFR conditions will prevail at all TAF sites through early Tuesday
morning. Northeasterly winds of 15 to 25kt will continue through
late this afternoon behind a weak cold front pushing southeast
across south central Kansas into Oklahoma. Winds will then subside
this evening while becoming more easterly as surface high pressure
moves from the Colorado Rockies into the Western High Plains.
Southerly winds of 10 to 20kt will develop early Tuesday morning
as the surface high shifts further east into eastern Kansas.
&&
.FIRE WEATHER...
ISSUED AT 414 AM CDT MON APR 21 2014
Elevated fire danger is expected for Tuesday as breezy southerly
winds and dew points in the 20s prevail through the day. A more
significant risk is expected Wednesday as a dryline moves as far
east as highway 283 by afternoon with strong gusty surface winds.
Fire weather watches and eventually red flag warnings may be
issued in the coming forecast shifts especially for areas west of
Highway 83 for Wednesday.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 76 45 80 56 / 10 0 0 10
GCK 75 45 82 57 / 10 0 10 10
EHA 74 50 83 58 / 10 0 10 10
LBL 76 48 83 58 / 10 0 0 10
HYS 75 43 75 56 / 80 0 10 20
P28 76 47 78 55 / 30 0 0 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...JJohnson
SHORT TERM...Gerard
LONG TERM...Russell
AVIATION...JJohnson
FIRE WEATHER...Russell
AREA FORECAST DISCUSSION
NWS PADUCAH KY
302 PM CDT Mon Apr 21 2014
.SHORT TERM...(Tonight through Wednesday night)
Issued at 301 PM CDT MON APR 21 2014
Radar has been showing light showers and sprinkles across parts of
the area all day, with the greatest concentration over southeast
Missouri and southwest IN. It it fairly dry in the lowest levels in
some places across the east, and sprinkles were noted in those
areas. Cold front is still poised well off to our west and will
continue making eastward progress later today and tonight. Short
term models have not done well with the ongoing precipitation. The
HRRR did pretty well early on but now the RAP models seems to be
doing ok. As the front approaches and until its departure, we will
continue to have scattered convection. The problem will be where and
when to place the best POPS as lift with this system is not too
strong. Will maintain at least scattered to likely wording for now.
With all the cloud cover, instability has been hard to come by, but
new thunderstorms are forming over northern Arkansas this afternoon,
which have some hope of moving into parts of the area.
Showers should quickly taper off from northwest to southeast between
05z and 10z Tuesday, with just a few showers possibly lingering in
our far southeast counties early Tuesday morning.
High pressure will build over the upper Mississippi valley Tuesday,
sliding slowly east over the Great Lakes region by Wednesday.
Winds out of the north on Tuesday will gradually shift to the east
by Wednesday, which will help give us cooler, near seasonal
conditions, as 900 mb temps drop back down into the single digits.
The region should see quite a bit of sunshine by Tuesday afternoon
and again on Wednesday with dry air in place over the area. Clouds
will increase late Wednesday night with increasing moisture ahead of
our next weather system.
.LONG TERM...(Thursday through Monday)
Issued at 301 PM CDT MON APR 21 2014
The 12Z models are in fairly good agreement in bringing the
southern end of a mid/upper level trough eastward through the
area, with a cold front, Thursday afternoon and evening. The upper
system is negatively tilted, so there should be enough forcing to
overcome very meager instability and create a band of showers and
thunderstorms near the front. Wind fields will be pretty good, but
instability is lacking, so would not expect much of a severe
threat. A stray strong storm cannot be ruled out, though. given
the speed of the system, would not expect much of a heavy rain
threat either.
The cold front Thursday is quite weak, so temperatures will still
be well into the 70s for highs on Friday with plenty of sunshine.
However, all bets are off beginning Friday night, as the models
diverge significantly in the details for our region. The GFS is
the most amplified in developing a Omega blocking pattern centered
on our region. It is particularly strong with its eastern trough,
and pushes a significant cold front through the area Friday night
and Saturday morning. This should be a dry frontal passage.
The GFS ends up with a very skinny ridge running northward right
through our region. This would keep the eastern half of the area
under the influence of the cool surface high and precipitation
free over the weekend. The question would be how much convective
activity would slip southeast over our western areas from Saturday
night on through Monday.
The ECMWF is quite a bit less amplified with the east coast
trough, and has varied considerably with the southward push of the
cold front. The 12Z version stalls the east-west oriented front
right through our region, and has a rather wet forecast from
Saturday night through at least Monday.
The GFS looks too amplified, but the ECMWF has not been very
consistent in its frontal/precipitation details. Will have small
pops mainly in the west Saturday night and Sunday, and then just
broad brush 30 to 40 PoPs for Sunday night through Monday night.
Temperatures will be tricky given the different synoptic
possibilities, but in general, they should be at or above normal
through Sunday and then fall below normal for Monday.
&&
.AVIATION...
Issued at 1230 PM CDT MON APR 21 2014
Scattered showers continue across southeast Missouri and are
working their way northeast. Additional showers are also trying to
develop over southwest IN. A front is poised well off to our
west...and the atmosphere will continue to moisten up in the lower
levels. Scattered rain showers and possible thunderstorms will be
possible for the rest of the afternoon. Tried to time the best
chances for precipitation near/along the front late this afternoon
and early this evening. Precip will shut off/move east of the area
later tonight and with the front passage will come a wind shift as well.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
SHORT TERM...DRS
LONG TERM...CW
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
417 PM EDT MON APR 21 2014
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 415 PM EDT MON APR 21 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A SPLIT FLOW REGIME ACROSS
THE CNTRL AND ERN CONUS. IN THE NRN STREAM...A VIGOROUS SHORTWAVE
WAS MOVING ACROSS NRN ONTARIO JUST TO THE N OF LAKE SUPERIOR. IN THE
SRN STREAM...ANOTHER WAVE WAS MOVING ACROSS THE MID AND LWR
MISSISSIPPI VALLEY. DESPITE STRENGTH AND PROXIMITY OF NRN STREAM
WAVE...IT`S ONLY BEEN IN THE LAST HR THAT ISOLD -SHRA HAVE MANAGED
TO DEVELOP ALONG ASSOCIATED SFC COLD FRONT WHICH IS RUNNING FROM
NEAR ISLE ROYALE ACROSS THE KEWEENAW AND THEN S THRU IRON COUNTY.
LIMITED COVERAGE IS DUE TO LACK OF INSTABILITY AND THE FACT THAT
DEEP LAYER FORCING WITH WAVE IS PASSING MOSTLY N OF UPPER MI.
OVER THE NEXT SEVERAL HRS...WILL CARRY MAINLY ISOLD -SHRA COVERAGE
ALONG COLD FRONT AS IT SWEEPS E. ATTENTION THEN TURNS TO HEALTHY CAA
AND LOW CLOUD/-FZDZ/DZ POTENTIAL. WITH 850MB TEMPS FALLING TO AROUND
-8C...LAKE EFFECT PCPN WON`T BE A CONCERN TONIGHT INTO TUE MORNING.
HOWEVER...MODELS CONTINUE TO SHOW SIGNIFICANT LOW-LEVEL MOISTENING
TONIGHT WHICH APPEARS ON TRACK GIVEN IFR CIGS THAT WERE OBSERVED
UPSTREAM IN NRN MN/ADJACENT ONTARIO EARLIER TODAY. DAYTIME HEATING
HAS RAISED CIGS...BUT CLOUDS CONTINUE TO HEAD SE EVEN THOUGH SLOWED
BY MIXING OUT OF MOISTURE AT THE LEADING EDGE. ONCE DAYTIME HEATING
DIMINISHES...CLOUDS WILL MAKE A QUICKER RUN TO THE SE INTO UPPER
MI. EXAMINATION OF FCST SOUNDINGS SHOW MOISTURE DEPTH INCREASES TO
800 TO 700MB...AND WITH TEMPS WITHIN THE MOISTURE DEPTH WARMER THAN
-10C...PRESENCE OF ICE CRYSTALS IS UNLIKELY. SO...IF THERE IS ANY
PCPN...PTYPE SHOULD BE JUST -DZ/-FZDZ. HOWEVER...SINCE MODEL TREND
HAS BEEN FOR MOISTURE DEPTH TO BE DEEPER AND CLOSER TO -10C...WILL
INCLUDE A MENTION OF FLURRIES AS WELL. WHILE CONFIDENCE IS NOT
HIGH...WILL CONTINUE WITH LOW POPS FOR -DZ/-FZDZ/FLURRIES
OVERNIGHT THRU TUE MORNING...MAINLY IN THE AREAS WHERE UPSLOPING
OCCURS WITH A NNW WIND. WITH THE BETTER MOISTURE OVER THE E...WILL
NOT MENTION ANY PCPN OVER THE FAR W.
ON TUE...IT APPEARS NOW THAT CLEARING TREND WILL BE SLOWER WITH
850MB TROF FIRMLY OVER THE FCST AREA AT 18Z. ANY LOCATIONS THAT
START THE DAY WITH SOME SUNSHINE WILL SEE CU/STRATOCU RAPIDLY
DEVELOP. DURING THE MID AND LATE AFTN...THE LAKE WILL BECOME A
STABILIZING INFLUENCE...RESULTING IN CLOUDS CLEARING OUT OVER THE
LAKE FIRST. THEN...THE CLEARING WILL SPREAD INLAND. WITH GRADIENT
N/NW WINDS ENHANCED BY LAKE BREEZE...IT WILL BE A BLUSTERY/SHARPLY
COLDER DAY WITH TEMPS 20 TO POSSIBLY AS MUCH AS 30 DEGREES COLDER IN
SOME SPOTS. IT WILL BE ESPECIALLY CHILLY ALONG LAKE SUPERIOR
WHERE TEMPS WON`T GET ABOVE THE MID 30S AT BEST. OVER THE FAR
SCNTRL...TEMPS MAY RISE TO AROUND 50F.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 409 PM EDT MON APR 21 2014
HIGH PRESSURE BUILDING INTO THE UPPER GREAT LAKES REGION ON TUESDAY
WILL LEAD TO A DRY PERIOD FOR TUESDAY NIGHT AND MUCH OF WEDNESDAY.
THERE MAY BE A FEW LINGERING CLOUDS OVER THE FAR EAST TO START THE
EVENING...BUT OTHERWISE EXPECT MOSTLY CLEAR SKIES TUESDAY NIGHT AND
INTO WEDNESDAY ACROSS THE U.P. LOWS ON TUESDAY NIGHT WILL BE BELOW
NORMAL AND IN THE 20S FOR MOST LOCATIONS. DID TREND SOME OF THE
INTERIOR COLD SPOTS IN THE TEENS SINCE THE HIGH WILL BE OVERHEAD
AND PWATS OF 40-45 PERCENT OF NORMAL WOULD SUPPORT GOING AT OR
BELOW MOS GUIDANCE. THE APRIL SUNSHINE SHOULD HELP WARM TEMPS BACK
CLOSER TO NORMAL FOR WEDNESDAY. LIGHT WINDS WILL GRADUALLY TURN TO
THE SOUTHEAST DURING THE AFTERNOON...BUT THEY SHOULD BE LIGHT
ENOUGH TO ALLOW LAKE BREEZES TO DEVELOP NEAR THE GREAT LAKES
SHORELINES AND KEEP TEMPERATURES COOLER THERE.
THE BULK OF THE LONG TERM FORECAST DEALS WITH AN UPPER LEVEL TROUGH
AND ASSOCIATED LOW PRESSURE SYSTEM THAT MOVES THROUGH THE GREAT
LAKES REGION WEDNESDAY NIGHT AND LIKELY CONTINUING INTO SATURDAY.
THIS UPPER TROUGH IS CURRENTLY WEST OF THE PACIFIC NORTHWEST AND
WILL COME ONSHORE TONIGHT. AS THIS SYSTEM CROSSES THE ROCKIES...A
SURFACE LOW WILL DEVELOP IN THE LEE OF THE CANADIAN/NORTHERN
ROCKIES AND SHIFT EAST INTO THE UPPER MISSISSIPPI VALLEY ON
THURSDAY. AS THIS OCCURS...BROAD ISENTROPIC ASCENT ON THE 290-305K
SURFACES WILL SPREAD NORTHEAST INTO UPPER MICHIGAN ON WEDNESDAY
NIGHT. THIS FIRST WAVE WILL STEADILY PUSH NORTHEAST THROUGH
THURSDAY...WHILE A SECONDARY WAVE OF PRECIPITATION MOVES IN ON
THURSDAY AHEAD OF THE UPPER TROUGH AXIS MOVES INTO THE UPPER
MISSISSIPPI VALLEY AND NEARS THE UPPER GREAT LAKES. THIS UPPER
TROUGH WILL SHIFT THE HEAVIEST PRECIPITATION OVER THE NORTHERN
HALF OF LAKE SUPERIOR THURSDAY NIGHT INTO FRIDAY...BUT WITH THE
MOISTURE PRESENT AND FORCING FROM THE UPPER TROUGH...WOULD EXPECT
LINGERING LIGHT SHOWERS TO BE ONGOING OVER THE AREA FRIDAY INTO
FRIDAY NIGHT. PRECIPITATION TYPE IS VERY TRICKY AT THIS POINT DUE TO
THE VARYING SOLUTIONS IN THE MODELS WITH THE THERMAL FIELD WEDNESDAY
NIGHT INTO THURSDAY. AS THE INITIAL SURGE OF PRECIP MOVES INTO THE
AREA...IT ENCOUNTERS A ISOTHERMAL LAYER FROM THE SURFACE THROUGH
700MB WITH TEMPERATURES AT OR JUST ABOVE FREEZING. THIS LAYER
REMAINS STEADY THROUGH MUCH OF THURSDAY. AS FOR THE MODELS...THE
12Z GFS HAS TRENDED A LITTLE COOLER COMPARED TO THE PREVIOUS
RUNS...THE 12Z ECMWF REMAINS THE COOLEST AND THE 12Z GEM IS
IN BETWEEN INITIALLY. UNFORTUNATELY IT IS DIFFICULT TO GET TOO
SPECIFIC IN THESE SITUATIONS AS JUST A SLIGHT CHANGE IN TEMPERATURE
BETWEEN 925-700MB OF 1-2C ONE WAY OR ANOTHER CAN MAKE A HUGE
DIFFERENCE IN THE PRECIP TYPE AND ASSOCIATED IMPACTS. THUS...WILL
FOLLOW AN IDEA OF RAIN/SNOW MIX WITH THE INITIAL SURGE OF PRECIP AND
LIKELY TRANSITIONING TO MORE RAIN DURING THE DAY THURSDAY (OVER
THE SOUTH HALF). THE NORTHWARD EXTENT OF THIS TRANSITION IS
UNCERTAIN AT THIS POINT AND WILL PLACE IT OVER THE NORTH HALF OF
LAKE SUPERIOR THURSDAY AFTERNOON/EVENING. COLDER AIR WILL BEGIN TO
SHIFT INTO THE AREA ON THURSDAY NIGHT AS THE LOW SHIFTS EAST ACROSS
UPPER MICHIGAN AND LEAD TO A TRANSITION TO ALL SNOW INTO FRIDAY. BY
THE TIME THE PRECIPITATION WILL START TO TRANSITION TO ALL
SNOW...THE HEAVIEST RATES WILL HAVE DEPARTED THE AREA AND EXPECT
MORE OF A SCATTERED/LIGHT PRECIP TO REMAIN. WILL CONTINUE THE
PREVIOUS SHIFTS IDEA OF THE HIGHEST QPF OVER THE WESTERN HALF OF
THE CWA AND AROUND 0.5-1.0IN THROUGH THURSDAY EVENING. THAT MATCHES
UP WELL WITH SOME OF THE ECMWF/GFS QPF PROBS. AS MENTIONED
EARLIER...SNOW POTENTIAL IS TRICKY BUT THE SLIGHTLY COOLER
TREND SEEN IN THE 12Z MODELS CREATES CONCERN FOR MEASURABLE (AND
POTENTIALLY SIGNIFICANT) SNOWFALL OVER THE KEWEENAW DUE TO ITS
CLOSER PROXIMITY TO THE COLDER AIR TO THE NORTH. FINALLY FOR THIS
SYSTEM...THE COLD AIR AND BREEZING CONDITIONS SURGING IN BEHIND THE
LOW ON FRIDAY AND INTO SATURDAY WILL MAKE IT FEEL MORE LIKE MARCH
ACROSS THE AREA. WIND CHILL VALUES FRIDAY NIGHT AND INTO SATURDAY
WILL BE IN THE TEENS AND 20S WITH THE LOWEST VALUES NEAR LAKE
SUPERIOR.
MODELS DO DIFFER ON HOW QUICKLY THE UPPER TROUGH DEPARTS THIS
WEEKEND...SO THE FORECAST FOR THE END OF THE WEEKEND AND INTO EARLY
NEXT WEEK IS UNCERTAIN. EVEN WITH THIS UNCERTAINTY...THE GENERAL
IDEA OF BELOW NORMAL TEMPERATURES FOR THE WEEKEND AND INTO THE FIRST
PART OF NEXT WEEK SEEMS REASONABLE AS A HUDSON BAY HIGH BECOMES
STATIONARY AND LEADS TO DRY NORTHEASTERLY FLOW. PRECIPITATION
CHANCES WILL DEPEND ON THE NEXT UPPER TROUGH THAT LOOKS TO BE
LOCATED IN THE CENTRAL/SOUTHERN PLAINS AND AT THIS TIME MAY BE FAR
ENOUGH SOUTH TO KEEP THE AREA DRY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 118 PM EDT MON APR 21 2014
DRY LOW-LEVEL AIR MASS WILL ALLOW VFR CONDITIONS TO CONTINUE THIS
AFTN AT KIWD/KCMX/KSAW. ALTHOUGH COLD FRONT HAS PASSED KIWD/KCMX AND
WILL REACH KSAW IN THE NEXT FEW HRS...DRY AIR MASS SHOULD PREVENT
ANY -SHRA FROM OCCURRING AT KSAW. TONIGHT...GUSTY NW WINDS THAT WILL
APPROACH 30KT AT THE MORE EXPOSED KCMX LOCATION WILL DRAW MUCH
COLDER AIR AS WELL AS LOW CLOUDS INTO THE UPPER LAKES. MVFR CIGS
WILL ARRIVE FIRST AT KCMX...EARLY THIS EVENING...AND THEN DURING THE
MID TO LATE EVENING AT KIWD/KSAW. CIGS WILL LIKELY FALL FURTHER TO
LOW MVFR AT KCMX/KSAW DURING THE NIGHT...AND IFR CIGS MAY EVENTUALLY
DEVELOP LATE. ARRIVAL OF DRIER AIR WILL RESULT IN CLOUDS CLEARING
OUT AT KIWD LATE TUE MORNING OR EARLY AFTN. CLEARING WILL OCCUR
LATER IN THE DAY AT KCMX/KSAW WITH KSAW THE LATEST.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 415 PM EDT MON APR 21 2014
IN THE WAKE OF A COLD FRONT CURRENTLY PASSING ACROSS LAKE
SUPERIOR...NW WINDS WILL INCREASE TO 15-30KT TONIGHT. STRONGEST
WINDS WILL BE IN A CORRIDOR FROM NCNTRL TO SCNTRL/SE LAKE SUPERIOR
WHERE SOME GALE FORCE GUSTS WILL PROBABLY OCCUR...MOSTLY IN THE
OVERNIGHT/EARLY TUE MORNING TIME PERIOD. THESE STONG WINDS WILL
DIMINISH FROM W TO E TUE INTO TUE EVENING AS A HIGH PRES RIDGE
ARRIVES. WINDS WILL FALL TO UNDER 15KT TUE NIGHT WITH LIGHT WINDS
LINGERING THRU AT LEAST WED MORNING AS HIGH PRES SLOWLY EXITS TO THE
E. OVER WRN LAKE SUPERIOR...NE WINDS WILL BE ON THE INCREASE WED
AFTN. AS ANOTHER LOW PRESSURE SYSTEM APPROACHES FROM THE PLAINS
LATER IN THE WEEK AND THE GRADIENT SHARPENS AGAIN...EASTERLY WINDS
WILL BE ON THE INCREASE THU. WINDS WILL THEN BACK AROUND TO THE N
FRI AS THE LOW PASSES ACROSS THE UPPER GREAT LAKES. DEPENDING ON THE
TRACK AND INTENSITY OF THIS LOW...THERE COULD SOME GALE FORCE
WINDS...POSSIBLY OVER WRN LAKE SUPERIOR AHEAD OF THE LOW AND THEN
OVER CNTRL AND ERN LAKE SUPERIOR AS THE LOW PASSES TO THE E.
&&
.HYDROLOGY...
ISSUED AT 409 PM EDT MON APR 21 2014
ANOTHER ABOVE NORMAL TEMPERATURE DAY WAS SEEN ACROSS UPPER MICHIGAN
TODAY...WITH HIGHS RISING INTO THE 50S TO LOWER 70S OVER MUCH OF
THE AREA. THESE WARM TEMPERATURES AND SUNSHINE HAS LIKELY LED TO
ANOTHER GOOD DAY OF MELTING IN THE AREAS THAT HAVE SNOW REMAINING.
STARTED TO SEE THE SECOND WAVE OF SNOW MELT RISES ON THE AREA
RIVERS YESTERDAY AND WILL CONTINUES TO SEE THAT INTO TONIGHT. BUT
COLDER TEMPERATURES EXPECTED TO ARRIVE ON TUESDAY SHOULD REALLY
SLOW THE MELT AND IN TURN LIMIT ADDITIONAL RISES. UNSETTLED WEATHER
WILL RETURN FROM THURSDAY THROUGH FRIDAY...ADDING TO THE RUNOFF. AT
THIS POINT THE BEST CHANCE OF SIGNIFICANT PRECIPITATION LOOKS TO BE
OVER THE WEST HALF OF UPPER MI...AND SPECIFICALLY THE KEWEENAW
PENINSULA...WHERE 0.50-1.00 INCH OF LIQUID WILL BE POSSIBLE BY
FRIDAY AFTERNOON. THERE IS SOME UNCERTAINTY ON HOW MUCH WILL FALL
AS RAIN AND HOW MUCH WILL FALL AS SNOW...BUT THE BEST CHANCE OF
SNOW WILL BE OVER THE KEWEENAW PENINSULA. WE WILL CONTINUE TO REFINE
THE FCST AS THE TIME NEARS.
SO FAR THE LOCATIONS EXPERIENCING SIGNIFICANT RISES HAVE BEEN
ALSTON/ALSM4/ ON THE STURGEON RIVER...ROCKLAND/RKLM4/ ON THE
ONTONAGON RIVER...CRYSTAL FALLS/CRYM4/ ON THE PAINT RIVER...AND TO A
LESSER EXTENT THE HYDE/FRDM4/ ON THE FORD RIVER (WHICH APPEARS TO
HAVE BEEN FROM AN ICE JAM).
WIDESPREAD FLOODING IS NOT FORESEEN AT THIS TIME...ALTHOUGH SOME
LOCATIONS MAY NEAR BANKFULL. HOWEVER...ANY RIVER THAT HAS ICE
REMAINING ON IT...ESPECIALLY THE ESCANABA RIVER IN DELTA
COUNTY...COULD EXPERIENCE AN ICE JAM WITH THE RISING RIVER
LEVELS THIS WEEK. THOSE LIVING AROUND RIVERS...CREEKS...AND STREAMS
SHOULD MONITOR BOTH RIVER LEVELS AND ICE CONDITIONS. ICE JAMS CAN
FORM AND BREAK QUICKLY...RESULTING IN RAPIDLY FLUCTUATING RIVER
LEVELS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...SRF
AVIATION...ROLFSON
MARINE...ROLFSON
HYDROLOGY...SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
410 PM EDT MON APR 21 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 424 AM EDT MON APR 21 2014
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW A SPLIT FLOW
REGIME ACRS THE CONUS WITH A STRONGER W-E POLAR BRANCH FLOW NEAR THE
CNDN BORDER TO THE N OF A WEAKER SRN BRANCH OVER THE SCENTRAL
STATES. SHRTWV RDG EMBEDDED IN THE POLAR BRANCH AND OVER NE MN/NW
ONTARIO AS WELL AS VERY DRY AIR SHOWN ON THE 00Z INL/MPX RAOBS ARE
BRINGING DRY WX TO UPR MI THIS MRNG EXCEPT OVER FAR SRN MENOMINEE
COUNTY...WHERE SOME ISOLD -SHRA ARE STILL PRESENT ON THE NRN EDGE OF
RIBBON OF DEEPER MSTR STRUNG W-E THRU THE CENTRAL LKS AND SAMPLED BY
THE FAIRLY MOIST 00Z GRB RAOB. MORE WDSPRD SHRA/EMBEDDED TS ARE
PRESENT OVER SW WI/FAR SE MN UNDER DEEPER MSTR/SOME UPR DVGC AHEAD
OF DISTURBANCE ON THE NRN EDGE OF SRN BRANCH FLOW. ALTHOUGH COLDER
CLOUD TOPS ARE EXPANDING TOWARD THE WI BORDER TO THE NE OF THESE
SHOWERS...THE LOWER LVL W FLOW OF VERY DRY AIR FM THE DIRECTION OF
MPX IS LIMITING THE N SPREAD OF THE SHRA LOCATED JUST S OF THAT RAOB
SITE. OTRW...SOME LOCALLY DENSE FOG HAS FORMED OVER THE CENTRAL/ERN
CWA AS THE DRIER AIR ALOFT MOVED OVER LOCATIONS THAT DID NOT SEE
SGNFT LLVL DRYING YDAY AFTN. OVER THE W WHERE SFC DEWPTS MIXED OUT
AS LO AS 25-30 AT IWD ON SUN AND TEMPS ARE STILL ABV 32 AT MOST
SPOTS...THERE IS LTL IF ANY FOG. A MUCH STRONGER SHRTWV IN THE POLAR
BRANCH FLOW IS NEAR LK WINNIPEG AND MOVING STEADILY TO THE E. THERE
HAVE BEEN SOME SHOWERS AND EVEN SOME LGT STRIKES IN MANITOBA RIGHT
UNDER THE STEEPER LAPSE RATES CLOSE TO THE CORE OF THIS DISTURBANCE.
BUT SINCE THIS SHRTWV IS CUTOFF FM THE MOISTER AIRMASS TO THE S...
THERE IS ONLY A NARROW BAND OF LIGHT SHOWERS ALONG ITS ATTENDANT
COLD FNT MOVING THRU NW MN EARLY THIS MRNG.
MAIN FCST CONCERNS IN THE SHORT TERM INVOLVE FOG EARLY THIS MRNG AND
THEN PCPN CHCS LATER TODAY/TNGT AS POLAR BRANCH SHRTWV/ATTENDANT
COLD FNT IMPACT UPR MI.
TODAY...EXPECT LOCALLY DENSE FOG TO PERSIST EARLY THIS MRNG OVER THE
SE HALF OF THE CWA...BUT INCRSG HI CLDS SHOULD LIMIT THE POTENTIAL
FOR WDSPRD DENSE FOG. WL ISSUE AN SPS TO ALERT THE PUBLIC TO LOCALLY
REDUCED VSBYS. SHRTWV NEAR LK WINNIPEG IS FCST TO MOVE E THRU NW
ONTARIO AND DRAG IT ATTENDANT COLD FNT ACRS UPR MI THIS AFTN. SINCE
BULK OF DPVA/DEEP LYR QVECTOR CNVGC WL REMAIN TO THE N AND JUST
BRUSH THE NRN LAND CWA...SUSPECT ONLY ISOLD-SCT SHOWERS WL ACCOMPANY
THE FROPA. ALMOST ALL THE MODELS THAT WERE SHOWING A GREATER
INTERACTION BTWN THIS SHRTWV/DEEPER MSTR TO THE S AND SGNFT
EXPANSION OF THIS MSTR/SHOWERS INTO UPR MI HAVE RETREATED A BIT FM
THIS FCST...A REASONABLE TREND CONSIDERING THE VERY DRY NATURE OF
THE 00Z MPX RAOB AND LACK OF SGNFT BACKING OF THE UPR FLOW FM THE W
THRU THE DAY. THE 00Z HI RES CNDN MODEL SHOWS THE HEAVIER PCPN
OVERSPREADING MOST OF UPR MI ALONG WITH THE MOST UNSTABLE MIXED LYR
CAPES AOA 1000 J/KG. FCST SDNGS FM THIS MODEL SHOW FAIRLY IMPRESSIVE
MOISTENING THRU THE LOWER TROP WITH SFC DEWPTS RISING TO ARND
55...WHICH DOES NOT SEEM RSNBL IN THE ABSENCE OF A DEEPER SW FLOW.
THE 00Z NAM SHOWS MORE MODEST MOISTENING/DESTABILIZATION OVER THE
SCENTRL. WL CARRY THE HIER CHC POPS THIS AFTN WHERE THIS MODEL SHOWS
THE GREATER INSTABILITY UP TO 700-800 J/KG OVER THE SCNTRL. INCLUDED
A SCHC OF TS IN THIS AREA AS WELL GIVEN ARRIVAL OF COLD FNT DURING
PEAK HEATING TIME THAT WL PUSH TEMPS WELL ABV NORMAL AGAIN IN THE
PRESENCE OF H85 TEMPS NOT FAR FM 10C AND AWAY FM THE MODERATING
INFLUENCE OF THE LKS. COOLER AIR WL ARRIVE OVER THE W LATER IN THE
DAY FOLLOWING THE FROPA.
TNGT...NW FLOW WITH H925 WINDS UP TO 25-35 KTS IN THE WAKE OF THE
COLD FROPA WL DRIVE COLDER AIR BACK INTO THE UPR LKS TNGT. MODELS
SHOW H85 TEMPS SINKING AS LO AS -7 TO -8C OVER THE W BY 12Z TUE.
WHILE THIS INCOMING AIRMASS WL NOT BE COLD ENUF FOR LK EFFECT
PCPN...MODELS DO SHOW SOME LLVL MOISTENING BLO STRENGTHENING
SUBSIDENCE INVRN ARND H85 UNDER THE LARGE SCALE QVECTOR DVGC LEFT IN
THE WAKE OF DEPARTING SHRTWV. GOING FCST SHOWS SOME DRIZZLE/FRZG
DRIZZLE OVER THE HIER TERRAIN WITH MOISTENING/INVRN BASE BLO THE
DGZ. THIS FCST SEEMS RSNBL...BUT DID ADD SOME FLURRIES AS WELL.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 409 PM EDT MON APR 21 2014
HIGH PRESSURE BUILDING INTO THE UPPER GREAT LAKES REGION ON TUESDAY
WILL LEAD TO A DRY PERIOD FOR TUESDAY NIGHT AND MUCH OF WEDNESDAY.
THERE MAY BE A FEW LINGERING CLOUDS OVER THE FAR EAST TO START THE
EVENING...BUT OTHERWISE EXPECT MOSTLY CLEAR SKIES TUESDAY NIGHT AND
INTO WEDNESDAY ACROSS THE U.P. LOWS ON TUESDAY NIGHT WILL BE BELOW
NORMAL AND IN THE 20S FOR MOST LOCATIONS. DID TREND SOME OF THE
INTERIOR COLD SPOTS IN THE TEENS SINCE THE HIGH WILL BE OVERHEAD
AND PWATS OF 40-45 PERCENT OF NORMAL WOULD SUPPORT GOING AT OR
BELOW MOS GUIDANCE. THE APRIL SUNSHINE SHOULD HELP WARM TEMPS BACK
CLOSER TO NORMAL FOR WEDNESDAY. LIGHT WINDS WILL GRADUALLY TURN TO
THE SOUTHEAST DURING THE AFTERNOON...BUT THEY SHOULD BE LIGHT
ENOUGH TO ALLOW LAKE BREEZES TO DEVELOP NEAR THE GREAT LAKES
SHORELINES AND KEEP TEMPERATURES COOLER THERE.
THE BULK OF THE LONG TERM FORECAST DEALS WITH AN UPPER LEVEL TROUGH
AND ASSOCIATED LOW PRESSURE SYSTEM THAT MOVES THROUGH THE GREAT
LAKES REGION WEDNESDAY NIGHT AND LIKELY CONTINUING INTO SATURDAY.
THIS UPPER TROUGH IS CURRENTLY WEST OF THE PACIFIC NORTHWEST AND
WILL COME ONSHORE TONIGHT. AS THIS SYSTEM CROSSES THE ROCKIES...A
SURFACE LOW WILL DEVELOP IN THE LEE OF THE CANADIAN/NORTHERN
ROCKIES AND SHIFT EAST INTO THE UPPER MISSISSIPPI VALLEY ON
THURSDAY. AS THIS OCCURS...BROAD ISENTROPIC ASCENT ON THE 290-305K
SURFACES WILL SPREAD NORTHEAST INTO UPPER MICHIGAN ON WEDNESDAY
NIGHT. THIS FIRST WAVE WILL STEADILY PUSH NORTHEAST THROUGH
THURSDAY...WHILE A SECONDARY WAVE OF PRECIPITATION MOVES IN ON
THURSDAY AHEAD OF THE UPPER TROUGH AXIS MOVES INTO THE UPPER
MISSISSIPPI VALLEY AND NEARS THE UPPER GREAT LAKES. THIS UPPER
TROUGH WILL SHIFT THE HEAVIEST PRECIPITATION OVER THE NORTHERN
HALF OF LAKE SUPERIOR THURSDAY NIGHT INTO FRIDAY...BUT WITH THE
MOISTURE PRESENT AND FORCING FROM THE UPPER TROUGH...WOULD EXPECT
LINGERING LIGHT SHOWERS TO BE ONGOING OVER THE AREA FRIDAY INTO
FRIDAY NIGHT. PRECIPITATION TYPE IS VERY TRICKY AT THIS POINT DUE TO
THE VARYING SOLUTIONS IN THE MODELS WITH THE THERMAL FIELD WEDNESDAY
NIGHT INTO THURSDAY. AS THE INITIAL SURGE OF PRECIP MOVES INTO THE
AREA...IT ENCOUNTERS A ISOTHERMAL LAYER FROM THE SURFACE THROUGH
700MB WITH TEMPERATURES AT OR JUST ABOVE FREEZING. THIS LAYER
REMAINS STEADY THROUGH MUCH OF THURSDAY. AS FOR THE MODELS...THE
12Z GFS HAS TRENDED A LITTLE COOLER COMPARED TO THE PREVIOUS
RUNS...THE 12Z ECMWF REMAINS THE COOLEST AND THE 12Z GEM IS
IN BETWEEN INITIALLY. UNFORTUNATELY IT IS DIFFICULT TO GET TOO
SPECIFIC IN THESE SITUATIONS AS JUST A SLIGHT CHANGE IN TEMPERATURE
BETWEEN 925-700MB OF 1-2C ONE WAY OR ANOTHER CAN MAKE A HUGE
DIFFERENCE IN THE PRECIP TYPE AND ASSOCIATED IMPACTS. THUS...WILL
FOLLOW AN IDEA OF RAIN/SNOW MIX WITH THE INITIAL SURGE OF PRECIP AND
LIKELY TRANSITIONING TO MORE RAIN DURING THE DAY THURSDAY (OVER
THE SOUTH HALF). THE NORTHWARD EXTENT OF THIS TRANSITION IS
UNCERTAIN AT THIS POINT AND WILL PLACE IT OVER THE NORTH HALF OF
LAKE SUPERIOR THURSDAY AFTERNOON/EVENING. COLDER AIR WILL BEGIN TO
SHIFT INTO THE AREA ON THURSDAY NIGHT AS THE LOW SHIFTS EAST ACROSS
UPPER MICHIGAN AND LEAD TO A TRANSITION TO ALL SNOW INTO FRIDAY. BY
THE TIME THE PRECIPITATION WILL START TO TRANSITION TO ALL
SNOW...THE HEAVIEST RATES WILL HAVE DEPARTED THE AREA AND EXPECT
MORE OF A SCATTERED/LIGHT PRECIP TO REMAIN. WILL CONTINUE THE
PREVIOUS SHIFTS IDEA OF THE HIGHEST QPF OVER THE WESTERN HALF OF
THE CWA AND AROUND 0.5-1.0IN THROUGH THURSDAY EVENING. THAT MATCHES
UP WELL WITH SOME OF THE ECMWF/GFS QPF PROBS. AS MENTIONED
EARLIER...SNOW POTENTIAL IS TRICKY BUT THE SLIGHTLY COOLER
TREND SEEN IN THE 12Z MODELS CREATES CONCERN FOR MEASURABLE (AND
POTENTIALLY SIGNIFICANT) SNOWFALL OVER THE KEWEENAW DUE TO ITS
CLOSER PROXIMITY TO THE COLDER AIR TO THE NORTH. FINALLY FOR THIS
SYSTEM...THE COLD AIR AND BREEZING CONDITIONS SURGING IN BEHIND THE
LOW ON FRIDAY AND INTO SATURDAY WILL MAKE IT FEEL MORE LIKE MARCH
ACROSS THE AREA. WIND CHILL VALUES FRIDAY NIGHT AND INTO SATURDAY
WILL BE IN THE TEENS AND 20S WITH THE LOWEST VALUES NEAR LAKE
SUPERIOR.
MODELS DO DIFFER ON HOW QUICKLY THE UPPER TROUGH DEPARTS THIS
WEEKEND...SO THE FORECAST FOR THE END OF THE WEEKEND AND INTO EARLY
NEXT WEEK IS UNCERTAIN. EVEN WITH THIS UNCERTAINTY...THE GENERAL
IDEA OF BELOW NORMAL TEMPERATURES FOR THE WEEKEND AND INTO THE FIRST
PART OF NEXT WEEK SEEMS REASONABLE AS A HUDSON BAY HIGH BECOMES
STATIONARY AND LEADS TO DRY NORTHEASTERLY FLOW. PRECIPITATION
CHANCES WILL DEPEND ON THE NEXT UPPER TROUGH THAT LOOKS TO BE
LOCATED IN THE CENTRAL/SOUTHERN PLAINS AND AT THIS TIME MAY BE FAR
ENOUGH SOUTH TO KEEP THE AREA DRY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 118 PM EDT MON APR 21 2014
DRY LOW-LEVEL AIR MASS WILL ALLOW VFR CONDITIONS TO CONTINUE THIS
AFTN AT KIWD/KCMX/KSAW. ALTHOUGH COLD FRONT HAS PASSED KIWD/KCMX AND
WILL REACH KSAW IN THE NEXT FEW HRS...DRY AIR MASS SHOULD PREVENT
ANY -SHRA FROM OCCURRING AT KSAW. TONIGHT...GUSTY NW WINDS THAT WILL
APPROACH 30KT AT THE MORE EXPOSED KCMX LOCATION WILL DRAW MUCH
COLDER AIR AS WELL AS LOW CLOUDS INTO THE UPPER LAKES. MVFR CIGS
WILL ARRIVE FIRST AT KCMX...EARLY THIS EVENING...AND THEN DURING THE
MID TO LATE EVENING AT KIWD/KSAW. CIGS WILL LIKELY FALL FURTHER TO
LOW MVFR AT KCMX/KSAW DURING THE NIGHT...AND IFR CIGS MAY EVENTUALLY
DEVELOP LATE. ARRIVAL OF DRIER AIR WILL RESULT IN CLOUDS CLEARING
OUT AT KIWD LATE TUE MORNING OR EARLY AFTN. CLEARING WILL OCCUR
LATER IN THE DAY AT KCMX/KSAW WITH KSAW THE LATEST.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 424 AM EDT MON APR 21 2014
LIGHT WINDS UNDER 15 KTS THIS MORNING ASSOCIATED WITH WEAK HIGH
PRESSURE RIDGE WILL SHIFT TO THE NW LATE TODAY/THIS EVENING
FOLLOWING A COLD FRONTAL PASSAGE AND INCREASE UP TO 25-30 KTS
TONIGHT AS MUCH COLDER AIR INVADES THE UPPER LAKES. NOT OUT OF THE
QUESTION THERE COULD BE SOME GALES OVER PORTIONS OF THE EAST HALF OF
THE LAKE UNDER THE SHARPER GRADIENT/STRONGEST LOW LEVEL WINDS.
MENTIONED SOME GALE FORCE GUSTS UP TO 35 KTS OVER THE ECENTRAL FOR
NOW. THESE STONG WINDS WILL DIMINISH TUE THRU WED AS A HI PRES RIDGE
AND WEAKER PRES GRADIENT MOVE OVER THE AREA. AS ANOTHER LOW PRESSURE
SYSTEM APPROACHES FROM THE PLAINS LATER IN THE WEEK AND THE GRADIENT
SHARPENS AGAIN...INCREASING SE WINDS WILL SHIFT TO THE NE. DEPENDING
ON THE TRACK AND INTENSITY OF THIS LO...THERE COULD BE AT LEAST A
PERIOD OF GALE FORCE WINDS.
&&
.HYDROLOGY...
ISSUED AT 409 PM EDT MON APR 21 2014
ANOTHER ABOVE NORMAL TEMPERATURE DAY WAS SEEN ACROSS UPPER MICHIGAN
TODAY...WITH HIGHS RISING INTO THE 50S TO LOWER 70S OVER MUCH OF
THE AREA. THESE WARM TEMPERATURES AND SUNSHINE HAS LIKELY LED TO
ANOTHER GOOD DAY OF MELTING IN THE AREAS THAT HAVE SNOW REMAINING.
STARTED TO SEE THE SECOND WAVE OF SNOW MELT RISES ON THE AREA
RIVERS YESTERDAY AND WILL CONTINUES TO SEE THAT INTO TONIGHT. BUT
COLDER TEMPERATURES EXPECTED TO ARRIVE ON TUESDAY SHOULD REALLY
SLOW THE MELT AND IN TURN LIMIT ADDITIONAL RISES. UNSETTLED WEATHER
WILL RETURN FROM THURSDAY THROUGH FRIDAY...ADDING TO THE RUNOFF. AT
THIS POINT THE BEST CHANCE OF SIGNIFICANT PRECIPITATION LOOKS TO BE
OVER THE WEST HALF OF UPPER MI...AND SPECIFICALLY THE KEWEENAW
PENINSULA...WHERE 0.50-1.00 INCH OF LIQUID WILL BE POSSIBLE BY
FRIDAY AFTERNOON. THERE IS SOME UNCERTAINTY ON HOW MUCH WILL FALL
AS RAIN AND HOW MUCH WILL FALL AS SNOW...BUT THE BEST CHANCE OF
SNOW WILL BE OVER THE KEWEENAW PENINSULA. WE WILL CONTINUE TO REFINE
THE FCST AS THE TIME NEARS.
SO FAR THE LOCATIONS EXPERIENCING SIGNIFICANT RISES HAVE BEEN
ALSTON/ALSM4/ ON THE STURGEON RIVER...ROCKLAND/RKLM4/ ON THE
ONTONAGON RIVER...CRYSTAL FALLS/CRYM4/ ON THE PAINT RIVER...AND TO A
LESSER EXTENT THE HYDE/FRDM4/ ON THE FORD RIVER (WHICH APPEARS TO
HAVE BEEN FROM AN ICE JAM).
WIDESPREAD FLOODING IS NOT FORESEEN AT THIS TIME...ALTHOUGH SOME
LOCATIONS MAY NEAR BANKFULL. HOWEVER...ANY RIVER THAT HAS ICE
REMAINING ON IT...ESPECIALLY THE ESCANABA RIVER IN DELTA
COUNTY...COULD EXPERIENCE AN ICE JAM WITH THE RISING RIVER
LEVELS THIS WEEK. THOSE LIVING AROUND RIVERS...CREEKS...AND STREAMS
SHOULD MONITOR BOTH RIVER LEVELS AND ICE CONDITIONS. ICE JAMS CAN
FORM AND BREAK QUICKLY...RESULTING IN RAPIDLY FLUCTUATING RIVER
LEVELS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...SRF
AVIATION...ROLFSON
MARINE...KC
HYDROLOGY...SRF
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
221 PM EDT MON APR 21 2014
LATEST UPDATE...
HYDRO
.SYNOPSIS...
ISSUED AT 318 AM EDT MON APR 21 2014
LOW PRESSURE MOVING ACROSS WISCONSIN AND LOWER MICHIGAN WILL BRING
LIGHT RAIN TO SW LOWER TODAY AND TONIGHT. THIS IS A VERY SLOW MOVING
SYSTEM AND GIVEN THE DRY AIR ALREADY IN PLACE...WE/RE NOT LOOKING AT
TOO MUCH RAIN...PERHAPS A QUARTER INCH. TEMPERATURES WILL CLIMB INTO
THE LOWER TO MID 70S AGAIN TODAY EXCEPT FOR AREAS NORTH OF US-10
WHERE 60S ARE EXPECTED. COOLER WEATHER CAN BE EXPECTED FOR THE
REMAINDER OF THE WEEK WITH MORE RAIN POSSIBLE THURSDAY INTO FRIDAY.
&&
.UPDATE...
ISSUED AT 925 AM EDT MON APR 21 2014
UPDATED FORECAST TO CUT POPS FOR THIS AFTERNOON BASED ON RADAR AND
LATEST HRRR WHICH SHOWS SHOWERS JUST ENTERING NORTHERN ILLINOIS
ATTM AND NOT ARRIVING UNTIL LATE AFTERNOON.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 318 AM EDT MON APR 21 2014
FORECAST CONCERNS DEAL WITH RAIN CHANCES TODAY AS A SLOW MOVING LOW
CROSSES WISCONSIN AND MICHIGAN.
THE LOW IN WISCONSIN WILL SLOWLY MOVE ACROSS NRN LWR TODAY. AHEAD OF
IT...WARM AIR WITH TEMPS IN THE 70S WILL BE NOTED. THE WARMER AIR
WILL BRING SOME ELEVATED INSTABILITY WITH IT...BUT NOTHING TOO
SIGNIFICANT. MUCAPE AROUND 500 J/KG AND LI/S SLIGHTLY BELOW 0C MAY
BE ENOUGH TO GENERATE A FEW STORMS. KEPT THE CHC OF THUNDER IN THE
GRIDS. FORECAST SOUNDINGS THIS AFTERNOON SHOW THE PRESENCE OF SOME
DRIER AIR IN THE LOWER TROP. THIS MAY RESULT IN SOME GUSTY WINDS AS
SHOWERS/STORMS MOVE ACROSS THE CWA.
THE LOW SHOULD MOVE OVER LAKE HURON BY MIDNIGHT AND COOLER AIR WILL
BEGIN TO FLOW BACK INTO THE CWA AS HIGH PRESSURE BUILDS INTO THE
GREAT LAKES. SUNSHINE WILL RETURN TUESDAY AND WEDNESDAY BUT HIGHS
WILL ONLY BE IN THE LOWER TO MID 50S.
.LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 318 AM EDT MON APR 21 2014
MODELS ARE IN FAIRLY GOOD AGREEMENT IN TRACKING A COLD FRONT THROUGH
THE REGION THU NIGHT. A SOUTHERLY LOW LEVEL JET MOVES IN AHEAD OF
THE COLD FRONT. THAT WILL ACT TO DEVELOP A BAND OF SHOWERS. THESE
SHOWERS WILL CROSS THE FORECAST AREA...WITH MOST LOCATIONS EXPECTED
TO SEE SOME PRECIPITATION. WILL KEEP POPS RELATIVELY HIGH THEN.
SOME INSTABILITY IS SHOWING UP IN THE MODELS WITH THIS RUN...SO WE
MAY NEED TO ADD THUNDER TO THE FORECAST.
BEHIND THE COLD FRONT IT WILL TURN WINDY ON FRIDAY. GUSTS OVER 35M
MPH LOOK LIKELY. AS THE UPPER LOW APPROACHES...SHOWERS SHOULD
DEVELOP ESPECIALLY IN THE AFTERNOON. THE HIGH RES EURO DOES SHOW A
MORE NORTHERLY TRACK TO THE IS UPPER LOW WITH THE 00Z MON RUN. THE
GFS IS STRONGER AND FURTHER SOUTH WITH THIS FEATURE AS COMPARED TO
THE HIGH RES EURO. FORECAST SOUNDINGS SHOW SOME CAPE DURING THE
AFTERNOON. MAY NEED TO ADD THUNDER TO THE FORECAST. SHOWERS LOOK
HIGH BASED GIVEN THE LARGE T/TD SPREAD AT THE SURFACE. I WILL
MAINTAIN THE RISK FOR SHOWERS IN THE FORECAST.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 122 PM EDT MON APR 21 2014
SHOWERS WILL GRADUALLY DEVELOP THIS AFTERNOON AND EVENING AND
CONDITIONS WILL GRADUALLY DETERIORATE FROM VFR TO MVFR AS LOWER
CLOUDS AND SHOWERS MOVE IN. CANNOT RULE OUT AN ISOLATED STORM LATE
THIS AFTERNOON AND EVENING BUT THERE IS NOT ENOUGH CONFIDENCE IN
CONVECTIVE POTENTIAL TO WARRANT INCLUSION IN THE TERMINAL FCSTS AT
THIS TIME. CONDITIONS WILL IMPROVE TO VFR TUESDAY AND WNW WINDS
WILL RAMP UP TO AROUND 15 TO 20 KTS WITH GUSTS TO 25 KTS BY LATE
MORNING.
&&
.HYDROLOGY...
ISSUED AT 220 PM EDT MON APR 21 2014
WARNINGS NO LONGER EXIST ON ANY OF THE AREA RIVERS OR STREAMS. ALL
HAVE SINCE BEEN DOWNGRADED TO ADVISORIES...WHICH ARE EVEN NUMBERED
THEMSELVES. SCOTTVILLE...CROTON AND EVART ARE THE HOLD OUTS WITH
THE ONGOING ADVISORIES. CONDITIONS CONTINUE TO IMPROVE WITH
DROPPING RIVER LEVELS BUT SOME LOCALIZED AFFECTS ARE STILL POSSIBLE.
WE WILL SEE A QUICK HIT OF RAINFALL THIS AFTERNOON THROUGH LATE THIS
EVENING. TOTAL RAINFALL AMOUNTS SHOULD REMAIN WELL SHY OF CREATING
ANY CONCERN FOR RIVERS AND STREAMS. THE NEXT CHANCE OF RAIN MOVES
IN BY THURSDAY AND FRIDAY.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
UPDATE...OSTUNO
SYNOPSIS...93
SHORT TERM...93
LONG TERM...MJS
AVIATION...LAURENS
HYDROLOGY...JAM
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
124 PM EDT MON APR 21 2014
LATEST UPDATE...
AVIATION
.SYNOPSIS...
ISSUED AT 318 AM EDT MON APR 21 2014
LOW PRESSURE MOVING ACROSS WISCONSIN AND LOWER MICHIGAN WILL BRING
LIGHT RAIN TO SW LOWER TODAY AND TONIGHT. THIS IS A VERY SLOW MOVING
SYSTEM AND GIVEN THE DRY AIR ALREADY IN PLACE...WE/RE NOT LOOKING AT
TOO MUCH RAIN...PERHAPS A QUARTER INCH. TEMPERATURES WILL CLIMB INTO
THE LOWER TO MID 70S AGAIN TODAY EXCEPT FOR AREAS NORTH OF US-10
WHERE 60S ARE EXPECTED. COOLER WEATHER CAN BE EXPECTED FOR THE
REMAINDER OF THE WEEK WITH MORE RAIN POSSIBLE THURSDAY INTO FRIDAY.
&&
.UPDATE...
ISSUED AT 925 AM EDT MON APR 21 2014
UPDATED FORECAST TO CUT POPS FOR THIS AFTERNOON BASED ON RADAR AND
LATEST HRRR WHICH SHOWS SHOWERS JUST ENTERING NORTHERN ILLINOIS
ATTM AND NOT ARRIVING UNTIL LATE AFTERNOON.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 318 AM EDT MON APR 21 2014
FORECAST CONCERNS DEAL WITH RAIN CHANCES TODAY AS A SLOW MOVING LOW
CROSSES WISCONSIN AND MICHIGAN.
THE LOW IN WISCONSIN WILL SLOWLY MOVE ACROSS NRN LWR TODAY. AHEAD OF
IT...WARM AIR WITH TEMPS IN THE 70S WILL BE NOTED. THE WARMER AIR
WILL BRING SOME ELEVATED INSTABILITY WITH IT...BUT NOTHING TOO
SIGNIFICANT. MUCAPE AROUND 500 J/KG AND LI/S SLIGHTLY BELOW 0C MAY
BE ENOUGH TO GENERATE A FEW STORMS. KEPT THE CHC OF THUNDER IN THE
GRIDS. FORECAST SOUNDINGS THIS AFTERNOON SHOW THE PRESENCE OF SOME
DRIER AIR IN THE LOWER TROP. THIS MAY RESULT IN SOME GUSTY WINDS AS
SHOWERS/STORMS MOVE ACROSS THE CWA.
THE LOW SHOULD MOVE OVER LAKE HURON BY MIDNIGHT AND COOLER AIR WILL
BEGIN TO FLOW BACK INTO THE CWA AS HIGH PRESSURE BUILDS INTO THE
GREAT LAKES. SUNSHINE WILL RETURN TUESDAY AND WEDNESDAY BUT HIGHS
WILL ONLY BE IN THE LOWER TO MID 50S.
.LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 318 AM EDT MON APR 21 2014
MODELS ARE IN FAIRLY GOOD AGREEMENT IN TRACKING A COLD FRONT THROUGH
THE REGION THU NIGHT. A SOUTHERLY LOW LEVEL JET MOVES IN AHEAD OF
THE COLD FRONT. THAT WILL ACT TO DEVELOP A BAND OF SHOWERS. THESE
SHOWERS WILL CROSS THE FORECAST AREA...WITH MOST LOCATIONS EXPECTED
TO SEE SOME PRECIPITATION. WILL KEEP POPS RELATIVELY HIGH THEN.
SOME INSTABILITY IS SHOWING UP IN THE MODELS WITH THIS RUN...SO WE
MAY NEED TO ADD THUNDER TO THE FORECAST.
BEHIND THE COLD FRONT IT WILL TURN WINDY ON FRIDAY. GUSTS OVER 35M
MPH LOOK LIKELY. AS THE UPPER LOW APPROACHES...SHOWERS SHOULD
DEVELOP ESPECIALLY IN THE AFTERNOON. THE HIGH RES EURO DOES SHOW A
MORE NORTHERLY TRACK TO THE IS UPPER LOW WITH THE 00Z MON RUN. THE
GFS IS STRONGER AND FURTHER SOUTH WITH THIS FEATURE AS COMPARED TO
THE HIGH RES EURO. FORECAST SOUNDINGS SHOW SOME CAPE DURING THE
AFTERNOON. MAY NEED TO ADD THUNDER TO THE FORECAST. SHOWERS LOOK
HIGH BASED GIVEN THE LARGE T/TD SPREAD AT THE SURFACE. I WILL
MAINTAIN THE RISK FOR SHOWERS IN THE FORECAST.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 122 PM EDT MON APR 21 2014
SHOWERS WILL GRADUALLY DEVELOP THIS AFTERNOON AND EVENING AND
CONDITIONS WILL GRADUALLY DETERIORATE FROM VFR TO MVFR AS LOWER
CLOUDS AND SHOWERS MOVE IN. CANNOT RULE OUT AN ISOLATED STORM LATE
THIS AFTERNOON AND EVENING BUT THERE IS NOT ENOUGH CONFIDENCE IN
CONVECTIVE POTENTIAL TO WARRANT INCLUSION IN THE TERMINAL FCSTS AT
THIS TIME. CONDITIONS WILL IMPROVE TO VFR TUESDAY AND WNW WINDS
WILL RAMP UP TO AROUND 15 TO 20 KTS WITH GUSTS TO 25 KTS BY LATE
MORNING.
&&
.HYDROLOGY...
ISSUED AT 1153 AM EDT SUN APR 20 2014
MINOR FLOODING EXISTS ON THE MUSKEGON RIVER AT CROTON AND EVART.
THE DOWNWARD TREND CONTINUES ON ALL AREA RIVERS AND TRIBUTARIES.
WE SHOULD SEE A FEW MORE ADVISORIES DROP OFF THE LIST OVER THE
NEXT 24 HOURS OR SO. HOWEVER...LOCAL IMPACTS MAY STILL BE EVIDENT
OVER THE NEXT SEVERAL DAYS ALONG THE MUSKEGON RIVER.
LIGHT RAIN IS POSSIBLE TONIGHT AHEAD OF A SLOW MOVING COLD FRONT.
BEST CHANCES TONIGHT SHOULD REMAIN ALONG AND NORTH OF HIGHWAY 10.
THE FRONT WILL FINALLY PUSH THROUGH MONDAY AFTERNOON AND THATS
WHEN RAIN IS MORE LIKELY THROUGHOUT THE AREA. PRECIPITATION
AMOUNTS WILL BE RATHER LIGHT AND SHOULD NOT HAVE ANY ADVERSE
AFFECTS ON RIVERS. ANOTHER SHOT OF RAIN WILL MOVE IN LATER IN THE
WORK WEEK BUT IT LOOKS LIKE THE HEAVIEST SHOULD REMAIN WEST OF
LOWER MICHIGAN.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
UPDATE...OSTUNO
SYNOPSIS...93
SHORT TERM...93
LONG TERM...MJS
AVIATION...LAURENS
HYDROLOGY...JAM
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
120 PM EDT MON APR 21 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 424 AM EDT MON APR 21 2014
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW A SPLIT FLOW
REGIME ACRS THE CONUS WITH A STRONGER W-E POLAR BRANCH FLOW NEAR THE
CNDN BORDER TO THE N OF A WEAKER SRN BRANCH OVER THE SCENTRAL
STATES. SHRTWV RDG EMBEDDED IN THE POLAR BRANCH AND OVER NE MN/NW
ONTARIO AS WELL AS VERY DRY AIR SHOWN ON THE 00Z INL/MPX RAOBS ARE
BRINGING DRY WX TO UPR MI THIS MRNG EXCEPT OVER FAR SRN MENOMINEE
COUNTY...WHERE SOME ISOLD -SHRA ARE STILL PRESENT ON THE NRN EDGE OF
RIBBON OF DEEPER MSTR STRUNG W-E THRU THE CENTRAL LKS AND SAMPLED BY
THE FAIRLY MOIST 00Z GRB RAOB. MORE WDSPRD SHRA/EMBEDDED TS ARE
PRESENT OVER SW WI/FAR SE MN UNDER DEEPER MSTR/SOME UPR DVGC AHEAD
OF DISTURBANCE ON THE NRN EDGE OF SRN BRANCH FLOW. ALTHOUGH COLDER
CLOUD TOPS ARE EXPANDING TOWARD THE WI BORDER TO THE NE OF THESE
SHOWERS...THE LOWER LVL W FLOW OF VERY DRY AIR FM THE DIRECTION OF
MPX IS LIMITING THE N SPREAD OF THE SHRA LOCATED JUST S OF THAT RAOB
SITE. OTRW...SOME LOCALLY DENSE FOG HAS FORMED OVER THE CENTRAL/ERN
CWA AS THE DRIER AIR ALOFT MOVED OVER LOCATIONS THAT DID NOT SEE
SGNFT LLVL DRYING YDAY AFTN. OVER THE W WHERE SFC DEWPTS MIXED OUT
AS LO AS 25-30 AT IWD ON SUN AND TEMPS ARE STILL ABV 32 AT MOST
SPOTS...THERE IS LTL IF ANY FOG. A MUCH STRONGER SHRTWV IN THE POLAR
BRANCH FLOW IS NEAR LK WINNIPEG AND MOVING STEADILY TO THE E. THERE
HAVE BEEN SOME SHOWERS AND EVEN SOME LGT STRIKES IN MANITOBA RIGHT
UNDER THE STEEPER LAPSE RATES CLOSE TO THE CORE OF THIS DISTURBANCE.
BUT SINCE THIS SHRTWV IS CUTOFF FM THE MOISTER AIRMASS TO THE S...
THERE IS ONLY A NARROW BAND OF LIGHT SHOWERS ALONG ITS ATTENDANT
COLD FNT MOVING THRU NW MN EARLY THIS MRNG.
MAIN FCST CONCERNS IN THE SHORT TERM INVOLVE FOG EARLY THIS MRNG AND
THEN PCPN CHCS LATER TODAY/TNGT AS POLAR BRANCH SHRTWV/ATTENDANT
COLD FNT IMPACT UPR MI.
TODAY...EXPECT LOCALLY DENSE FOG TO PERSIST EARLY THIS MRNG OVER THE
SE HALF OF THE CWA...BUT INCRSG HI CLDS SHOULD LIMIT THE POTENTIAL
FOR WDSPRD DENSE FOG. WL ISSUE AN SPS TO ALERT THE PUBLIC TO LOCALLY
REDUCED VSBYS. SHRTWV NEAR LK WINNIPEG IS FCST TO MOVE E THRU NW
ONTARIO AND DRAG IT ATTENDANT COLD FNT ACRS UPR MI THIS AFTN. SINCE
BULK OF DPVA/DEEP LYR QVECTOR CNVGC WL REMAIN TO THE N AND JUST
BRUSH THE NRN LAND CWA...SUSPECT ONLY ISOLD-SCT SHOWERS WL ACCOMPANY
THE FROPA. ALMOST ALL THE MODELS THAT WERE SHOWING A GREATER
INTERACTION BTWN THIS SHRTWV/DEEPER MSTR TO THE S AND SGNFT
EXPANSION OF THIS MSTR/SHOWERS INTO UPR MI HAVE RETREATED A BIT FM
THIS FCST...A REASONABLE TREND CONSIDERING THE VERY DRY NATURE OF
THE 00Z MPX RAOB AND LACK OF SGNFT BACKING OF THE UPR FLOW FM THE W
THRU THE DAY. THE 00Z HI RES CNDN MODEL SHOWS THE HEAVIER PCPN
OVERSPREADING MOST OF UPR MI ALONG WITH THE MOST UNSTABLE MIXED LYR
CAPES AOA 1000 J/KG. FCST SDNGS FM THIS MODEL SHOW FAIRLY IMPRESSIVE
MOISTENING THRU THE LOWER TROP WITH SFC DEWPTS RISING TO ARND
55...WHICH DOES NOT SEEM RSNBL IN THE ABSENCE OF A DEEPER SW FLOW.
THE 00Z NAM SHOWS MORE MODEST MOISTENING/DESTABILIZATION OVER THE
SCENTRL. WL CARRY THE HIER CHC POPS THIS AFTN WHERE THIS MODEL SHOWS
THE GREATER INSTABILITY UP TO 700-800 J/KG OVER THE SCNTRL. INCLUDED
A SCHC OF TS IN THIS AREA AS WELL GIVEN ARRIVAL OF COLD FNT DURING
PEAK HEATING TIME THAT WL PUSH TEMPS WELL ABV NORMAL AGAIN IN THE
PRESENCE OF H85 TEMPS NOT FAR FM 10C AND AWAY FM THE MODERATING
INFLUENCE OF THE LKS. COOLER AIR WL ARRIVE OVER THE W LATER IN THE
DAY FOLLOWING THE FROPA.
TNGT...NW FLOW WITH H925 WINDS UP TO 25-35 KTS IN THE WAKE OF THE
COLD FROPA WL DRIVE COLDER AIR BACK INTO THE UPR LKS TNGT. MODELS
SHOW H85 TEMPS SINKING AS LO AS -7 TO -8C OVER THE W BY 12Z TUE.
WHILE THIS INCOMING AIRMASS WL NOT BE COLD ENUF FOR LK EFFECT
PCPN...MODELS DO SHOW SOME LLVL MOISTENING BLO STRENGTHENING
SUBSIDENCE INVRN ARND H85 UNDER THE LARGE SCALE QVECTOR DVGC LEFT IN
THE WAKE OF DEPARTING SHRTWV. GOING FCST SHOWS SOME DRIZZLE/FRZG
DRIZZLE OVER THE HIER TERRAIN WITH MOISTENING/INVRN BASE BLO THE
DGZ. THIS FCST SEEMS RSNBL...BUT DID ADD SOME FLURRIES AS WELL.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 543 AM EDT MON APR 21 2014
SFC TEMPS SHOULD WARM QUICKLY TUESDAY MORNING...LIMITING THE
POTENTIAL FOR FREEZING DRIZZLE. WILL STILL KEEP DRIZZLE GOING GIVEN
THE LIMITED LIKELIHOOD OF ICE CRYSTALS IN THE SOUNDING. OTHERWISE
COOL N-NW WINDS WILL BE THE RULE...WITH 850MB TEMPS IN THE -6 TO -8C
RANGE HELPING TO KEEP MAX SFC TEMPS TUESDAY IN THE UPPER 30S TO MID
40S OVER MUCH OF THE CWA.
DRY HIGH PRESSURE OVERHEAD TUESDAY NIGHT INTO WEDNESDAY WILL RESULT
IN NEARLY CALM WINDS WEDNESDAY MORNING. WITH FEW IF ANY CLOUDS
AROUND AND PW VALUES FALLING TO AROUND 45 PERCENT OF NORMAL /0.25IN/
SHOULD ALLOW TEMPS TO FALL INTO THE 20S TUESDAY NIGHT/WEDNESDAY
MORNING.
PLENTY OF UNCERTAINTY REMAINS WITH OUR END OF THE WEEK SYSTEM. WHILE
POPS HAVE BEEN INCREASED AND MUCH OF THE FOCUS FOR MODERATE TO HEAVY
PRECIP REMAINS OVER THE W HALF OF UPPER MI...THE 21/00Z RUN OF THE
ECMWF HAS BACKED AWAY FROM THE DEEPER MORE WRAPPED UP SFC LOW THAT
IT/S 20/12Z RUN INDICATED. STILL...ALL INDICATIONS ARE THAT 0.5-1IN
OF LIQUID WILL BE POSSIBLE NEAR AND W OF A LINE FROM MQT TO MNM
THURSDAY INTO THURSDAY NIGHT. THE ECMWF ENSEMBLES HAVE 30-40 PERCENT
CHANCE OF SEEING 1IN OR MORE OVER THE W HALF. GIVEN THAT MUCH OF THE
SYSTEM IS AROUND 84HRS OR MORE INTO THE FUTURE...WILL CONTINUE WITH
A MORE BROAD/AVERAGED SOLUTION AT THIS POINT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 118 PM EDT MON APR 21 2014
DRY LOW-LEVEL AIR MASS WILL ALLOW VFR CONDITIONS TO CONTINUE THIS
AFTN AT KIWD/KCMX/KSAW. ALTHOUGH COLD FRONT HAS PASSED KIWD/KCMX AND
WILL REACH KSAW IN THE NEXT FEW HRS...DRY AIR MASS SHOULD PREVENT
ANY -SHRA FROM OCCURRING AT KSAW. TONIGHT...GUSTY NW WINDS THAT WILL
APPROACH 30KT AT THE MORE EXPOSED KCMX LOCATION WILL DRAW MUCH
COLDER AIR AS WELL AS LOW CLOUDS INTO THE UPPER LAKES. MVFR CIGS
WILL ARRIVE FIRST AT KCMX...EARLY THIS EVENING...AND THEN DURING THE
MID TO LATE EVENING AT KIWD/KSAW. CIGS WILL LIKELY FALL FURTHER TO
LOW MVFR AT KCMX/KSAW DURING THE NIGHT...AND IFR CIGS MAY EVENTUALLY
DEVELOP LATE. ARRIVAL OF DRIER AIR WILL RESULT IN CLOUDS CLEARING
OUT AT KIWD LATE TUE MORNING OR EARLY AFTN. CLEARING WILL OCCUR
LATER IN THE DAY AT KCMX/KSAW WITH KSAW THE LATEST.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 424 AM EDT MON APR 21 2014
LIGHT WINDS UNDER 15 KTS THIS MORNING ASSOCIATED WITH WEAK HIGH
PRESSURE RIDGE WILL SHIFT TO THE NW LATE TODAY/THIS EVENING
FOLLOWING A COLD FRONTAL PASSAGE AND INCREASE UP TO 25-30 KTS
TONIGHT AS MUCH COLDER AIR INVADES THE UPPER LAKES. NOT OUT OF THE
QUESTION THERE COULD BE SOME GALES OVER PORTIONS OF THE EAST HALF OF
THE LAKE UNDER THE SHARPER GRADIENT/STRONGEST LOW LEVEL WINDS.
MENTIONED SOME GALE FORCE GUSTS UP TO 35 KTS OVER THE ECENTRAL FOR
NOW. THESE STONG WINDS WILL DIMINISH TUE THRU WED AS A HI PRES RIDGE
AND WEAKER PRES GRADIENT MOVE OVER THE AREA. AS ANOTHER LOW PRESSURE
SYSTEM APPROACHES FROM THE PLAINS LATER IN THE WEEK AND THE GRADIENT
SHARPENS AGAIN...INCREASING SE WINDS WILL SHIFT TO THE NE. DEPENDING
ON THE TRACK AND INTENSITY OF THIS LO...THERE COULD BE AT LEAST A
PERIOD OF GALE FORCE WINDS.
&&
.HYDROLOGY...
ISSUED AT 1202 AM EDT MON APR 21 2014
HIGHEST SNOW DEPTH REPORTED YESTERDAY MORNING OF 32IN AT MOHAWK WAS
ABLE TO DROP DOWN TO 28IN BY LATE EVENING. AT THE OTHER END OF THE
SPECTRUM...SEVERAL SITES FROM IWD THROUGH ISQ WERE REPORTING LITTLE
TO NO SNOW. TODAY WILL BE ANOTHER DAY OF MELTING...AS HIGH
TEMPERATURES JUMP INTO THE 50S AND LOW 60S FOR MUCH OF THE AREA. THE
MELT WILL SLOW TUESDAY-TUESDAY NIGHT OVER N UPPER MI AS COLD N-NNW
WINDS KEEP TEMPS TOPPING OUT IN THE 30S AND LOW 40S TUESDAY. AS FOR
FURTHER OUT...TEMPERATURES WILL RETURN TO NEAR NORMAL VALUES
TEMPORARILY WEDNESDAY BEFORE FALLING BACK INTO THE 30S AND 40S
THROUGH THE UPCOMING WEEKEND.
WILL CONTINUE TO NOTICE SIGNIFICANT STREAM/RIVER RISES OVER THE NEXT
FEW DAYS. UNSETTLED WEATHER WILL RETURN FROM THURSDAY THROUGH
FRIDAY...ADDING TO THE RUNOFF. AT THIS POINT THE BEST CHANCE OF
SIGNIFICANT PRECIPITATION LOOKS TO BE OVER THE W HALF OF UPPER
MI...AND SPECIFICALLY THE KEWEENAW PENINSULA WHERE 0.75-1IN OF
LIQUID WILL BE POSSIBLE BY FRIDAY AFTERNOON. WE WILL CONTINUE TO
REFINE THE FCST AS THE TIME NEARS.
SO FAR THE LOCATIONS EXPERIENCING SIGNIFICANT RISES HAVE BEEN
ALSTON/ALSM4/ ON THE STURGEON RIVER...ROCKLAND/RKLM4/ ON THE
ONTONAGON RIVER...AND TO A LESSER EXTENT THE HYDE/FRDM4/ ON THE FORD
RIVER.
WIDESPREAD FLOODING IS NOT FORESEEN AT THIS TIME. HOWEVER...ANY
RIVER THAT HAS ICE REMAINING ON IT...ESPECIALLY THE ESCANABA RIVER
IN DELTA COUNTY...COULD EXPERIENCE AN ICE JAM WITH THE RISING RIVER
LEVELS THIS WEEK. THOSE LIVING AROUND RIVERS...CREEKS...AND STREAMS
SHOULD MONITOR BOTH RIVER LEVELS AND ICE CONDITIONS. ICE JAMS CAN
FORM AND BREAK QUICKLY...RESULTING IN RAPIDLY FLUCTUATING RIVER
LEVELS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...KF
AVIATION...ROLFSON
MARINE...KC
HYDROLOGY...KF
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1252 PM CDT MON APR 21 2014
.UPDATE...
ISSUED AT 1252 PM CDT MON APR 21 2014
A NARROW STRIP OF CLOUDS EXTENDED FROM CROSBY TO TIOGA...SOUTH
THROUGH CENTER AND BISMARCK. THESE CLOUDS SHOULD ERODE WITHIN THE
NEXT HOUR OR TWO AS SYNOPTIC SUBSIDENCE SPREADS OVER THE REGION.
UPDATED THE FORECAST TO REMOVE MORNING WORDING AND INDICATED
MOSTLY SUNNY SKIES OVER WESTERN AND CENTRAL NORTH DAKOTA. THE
REMAINING FORECAST ELEMENTS ARE IN GOOD SHAPE. THE UPDATED
PRODUCTS HAVE BEEN SENT.
UPDATE ISSUED AT 1003 AM CDT MON APR 21 2014
UPDATED THE FORECAST TO INCREASE CLOUD COVER OVER THE
SOUTHEASTERN CWA THIS MORNING BASED ON THE TRAJECTORY OF LOW
STRATUS ROTATING SOUTHEAST ACROSS WESTERN AND CENTRAL NORTH
DAKOTA. STRONG SYNOPTIC SUBSIDENCE OVERSPREADING THE REGION SHOULD
ERODE THIS CLOUD DECK BY EARLY AFTERNOON. OTHERWISE...THE
REMAINING FORECAST ELEMENTS ARE IN GOOD SHAPE. THE UPDATED
PRODUCTS HAVE BEEN SENT.
UPDATE ISSUED AT 625 AM CDT MON APR 21 2014
ONLY CHANGES TO FORECAST WERE TO POPULATE WITH LATEST HOURLY
OBSERVATIONS. TEMPS WERE RUNNING A LITTLE COLDER THAN FORECAST IN
A FEW LOCATIONS. OTHERWISE...LOW STRATUS CONTINUES TO SLOWLY PUSH
SOUTHWARD WHICH IS HANDLED WELL IN FORECAST.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 348 AM CDT MON APR 21 2014
NO MAJOR FORECAST HIGHLIGHTS IN THE SHORT TERM PERIOD.
CURRENTLY...QUASI-ZONAL FLOW ACROSS THE NORTHERN PLAINS WITH A
STRONG EMBEDDED S/WV TROUGH PUSHING EAST ALONG THE INTERNATIONAL
BORDER...NOW CENTERED NEAR TO EAST OF LAKE WINNIPEG. WRAP AROUND
MOISTURE IN THE FORM OF LOW LEVEL STRATUS SURGING SOUTH AND EAST
ACROSS MY NORTHERN COUNTIES THE PAST COUPLE OF HOURS. AT THIS TIME
DO NOT ANTICIPATE ANY PRECIPITATION ASSOCIATED WITH THE STRATUS.
WILL CONTINUE TO MONITOR.
LOW BKN-OVC CLOUDS WILL CONTINUE TO MOVE ACROSS NORTHWEST AND
NORTH CENTRAL NORTH DAKOTA NOW THROUGH 10Z...EVENTUALLY DEPICTED
BY BOTH THE RAP AND 00Z/06Z NAM TO PUSH AS FAR SOUTH AS BISMARCK
AND JAMESTOWN 10-14Z. AFTERWARDS...STRATUS SHOULD DISSIPATE/BURN
OFF BY THE EARLY AFTERNOON. THE MORNING CLOUDS COUPLED WITH CAA
THE PAST SEVERAL HOURS WILL RESULT IN HIGH TEMPERATURES TODAY IN
THE 50S ALONG TO NORTH AND EAST OF THE MISSOURI RIVER...60S SOUTH
AND WEST OF THE MISSOURI.
RETURN FLOW/WAA TONIGHT AS AN UPPER LEVEL RIDGE OF HIGH PRESSURE
AMPLIFIES ACROSS THE ROCKIES TODAY THEN PROPAGATES EAST INTO THE
HIGH PLAINS TONIGHT.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 348 AM CDT MON APR 21 2014
ACTIVE PERIOD EXPECTED WITH STRONG STORM SYSTEM APPROACHING THE
REGION TUESDAY NIGHT. LARGE SURFACE LOW INITIALLY CENTERED OVER
CENTRAL MONTANA 00Z WEDNESDAY TRANSITIONS TO DUAL SURFACE LOWS
OVER SOUTHEASTERN SASKATCHEWAN AND SOUTHEAST MONTANA BY 12Z WED AS
SHORTWAVE/90KT H250 JET STREAK ROTATE AROUND PARENT UPPER LOW.
BREEZY TO WINDY EAST/SOUTHEAST WINDS WILL OCCUR ALSO WITH TIGHT
SURFACE GRADIENT AND 850MB WINDS TO 45KTS LATE TUESDAY AND TUESDAY
NIGHT. SPC CONTINUES TO INCLUDE THE WESTERN HALF OF THE STATE IN
GENERAL THUNDERSTORM AREA WITH MODELS INDICATING LOW CAPE NUDGING
INTO THIS REGION ALONG WITH H7-H5 LAPSE RATES APPROACHING 8C/KM
TUESDAY NIGHT AHEAD OF THE COLD FRONT. MODELS CONTINUE TO SHOW
HIGHEST QPF ACROSS NORTH AND EAST AS DRY SLOT IS MORE OF A FACTOR
ACROSS WESTERN AND SOUTHERN AREAS. WEDNESDAY NIGHT INTO THURSDAY
THE CLOSED UPPER LOW AND ASSOCIATED SURFACE LOW MOVE ACROSS THE
NORTHERN PLAINS. MODEL DIFFERENCES INCREASE WITH THIS FEATURE WITH
THE GFS A LITTLE FASTER AND FARTHER SOUTH COMPARED TO ECMWF. BOTH
MODELS...HOWEVER...BRING SUB 0C H850 AIR ACROSS THE STATE IN
NORTHERLY FLOW BEHIND THE SYSTEM THURSDAY NIGHT WITH LIGHT PRECIP
IN THE FORM OF RAIN CHANGING TO SNOW FROM NORTH TO SOUTH.
SUBSTANTIAL MODEL DIFFERENCES BY NEXT WEEKEND WITH GFS SHOWING
STRONGER RIDGE AND DRYER WEATHER OVER ND ON SATURDAY WHILE ECMWF
HAS LESS AMPLIFIED PATTERN AND ANOTHER BATCH OF PRECIP MOVING IN
UNDER SOUTHWEST FLOW ALOFT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1252 PM CDT MON APR 21 2014
MVFR CIGS OVER KBIS SHOULD BECOME VFR BY 19Z. OTHERWISE...VFR
CONDITIONS WILL PREVAIL OVER WESTERN AND CENTRAL NORTH DAKOTA
THROUGH THE TAF PERIOD.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...TM
SHORT TERM...NH
LONG TERM...JNS
AVIATION...TM
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
313 PM CDT MON APR 21 2014
.DISCUSSION...
FORECAST REASONING WILL LEAN TOWARD A CONSENSUS MODEL SOLUTION
COMPROMISE FOR THE FORECAST PERIOD UNLESS OTHERWISE NOTED.
FORECAST QUANDARIES...WX PATTERN TONIGHT THRU TUE...WX PATTERN LATE
THIS WEEKEND INTO THE FIRST PART OF NEXT WEEK...TEMPS.
MODELS CONTINUING THEIR RECENT TREND OFF OVERALL WEAKENING OF THE
FRONTAL SYSTEM EXPECTED TO BEGIN TO INFLUENCES THE MID STATE`S WX
TONIGHT...STILL LOOKING LIKE IT WILL BE MAINLY AFTER MIDNIGHT...
AS A SFC COLD FRONT APPROACHES THE MID STATE FROM THE NW BY
22/12Z. LATEST SHORT RANGE MODELS INCLUDING THE HRRR SHOWING EVEN
THE POSSIBILITY OF THIS ACTIVITY MAINLY MOVING S OF THE MID STATE
TOO. ALTHOUGH MODEL SOUNDING SHOWING LITTLE IN THE WAY OF OVERALL
ATM INSTABILITY...WITH UPPER LEVEL TROUGH PASSAGE EXPECTED ACROSS
MOST OF THE MID STATE BY 22/12Z ALSO...CAN NOT RULE OUT A RUMBLE
OF THUNDER HERE OR THERE MAINLY AFTER MIDNIGHT TONIGHT...BUT
BELIEVE THAT MOST OF THE ACTIVITY WILL BE IN THE FORM OF SHWRS
MAINLY AFTER MIDNIGHT ALSO. AS FOR RAINFALL AMOUNTS...EXPECT
GENERALLY LESS THAN ONE HALF OF AN INCH IN MOST LOCATIONS. AS FOR
TEMPS...WITH ADDITIONAL CLOUD COVERAGE...RAINFALL...AND A
CONTINUANCE OF SWLY WIND FLOW EXPECTED...TAPPING INTO A SLIGHTLY
WARMER AIRMASS TO OUR SW ALSO...WILL GO CLOSE TO AN MOS GUIDANCE
CONSENSUS SOLUTION. EXPECT NUMEROUS SHWRS AND ISO TSTMS TO
CONTINUE ACROSS THE MID STATE DURING THE MORNING HRS ON TUE AS
SFC FRONT MOVES THRU THE MID STATE DURING THE MORNING HRS...WITH
A SLIGHT CHANCE OF SHWRS/TSTMS POSSIBLY PERSISTING ACROSS THE
PLATEAU AND SRN COUNTIES. EXPECT A SLIGHT COOL DOWN IN HIGHS FROM
THIS AFTERNOON`S VALUES...AND WILL AGAIN GO CLOSE TO CONSENSUS
MODEL REASONING ON TEMPS...WITH HIGHS MAINLY IN THE LOWER 70S.
RIDGING INFLUENCES SFC AND ALOFT WILL PROVIDE DRY CONDITIONS WITH
LOWS MAINLY IN THE LOWER 40S WED MORNING...HIGHS NEAR SEASONABLE
NORMAL VALUES ON WED...AND A RETURN TO TEMPS MAINLY IN THE LOW TO
MID 40S ON WED NIGHT.
TAKING A LOOK AT THE REST OF THE FORECAST PERIOD...THU THRU THE FIRST
PORTION OF NEXT WEEK...STILL EXPECTING A FRONTAL SYSTEM TO MOVE THRU
THE MID STATE MAINLY ON THU NIGHT...WITH SOME STRONG TSTMS POSSIBLE...
BUT MODEL TRENDING TOWARD THIS POSSIBILITY BECOMING MORE AND MORE ISO
IN NATURE. AFTER THE FRONTAL PASSAGE DURING THE MORNING HRS ON FRI...
CANADIAN BASED SFC RIDGING INFLUENCES SHOULD PROVIDE FOR DRY CONDITIONS
THRU AT LEAST THE FIRST HALF OF SUN. THERE HAVE BEEN SOME DIFFERENCES
IN THE MODELS AS OF LATE DEALING WITH THE OVERALL WX PATTERN FOR THE
SECOND HALF OF SUN INTO THE FIRST PART OF NEXT WEEK...BUT MODEL GUIDANCE
STARTING TO COME MORE IN LINE WITH EACH OTHER. SHWRS/TSTMS SHOULD
AGAIN DEVELOP ON SUN NIGHT/MON AS A WELL ORGANIZED FRONTAL SYSTEM
PUSHES A WARM FRONT FROM THE S INTO THE MID STATE PUTTING THE MID
STATE IN THE BROAD WARM SECTOR OF THIS DEVELOPING POTENTIALLY STRONG
FRONTAL SYSTEM. AS FOR TEMPS...HIGHS WILL CONTINUE AT LEAST SLIGHTLY
ABOVE SEASONAL NORMAL VALUES THRU SAT...MAINLY IN THE MID TO UPPER
70S...COOLING BACK TO MORE SEASONABLE NORMAL VALUES BY THE FIRST
PART OF NEXT WEEK.
&&
.PRELIMINARY POINT TEMPS/POPS...
NASHVILLE 60 72 44 69 / 60 60 0 0
CLARKSVILLE 58 72 41 69 / 60 20 0 0
CROSSVILLE 56 70 39 66 / 60 60 0 0
COLUMBIA 60 73 45 71 / 60 60 0 0
LAWRENCEBURG 59 73 44 73 / 60 60 0 0
WAVERLY 59 72 42 70 / 60 50 0 0
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
31
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1255 PM CDT MON APR 21 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 323 AM CDT MON APR 21 2014
THE MAIN FOCUS THROUGH TONIGHT IS ON THE TIMING OF THE COLD FRONT
PASSAGE AND THE CONVECTION THAT IS EXPECTED TO DEVELOP AHEAD OF IT
TODAY.
SHOWERS AND SOME THUNDERSTORMS CONTINUE ACROSS MUCH OF THE REGION
WHICH IS IN A BROAD CHANNEL OF LOW LEVEL MOISTURE TRANSPORT AHEAD
OF A SURFACE COLD FRONT. THE 21.07Z RAP ANALYSIS SHOWS THAT THE
HIGHEST 0-3KM MUCAPE OF A FEW HUNDRED J/KG IS ACROSS SOUTH
CENTRAL MINNESOTA AND NORTH CENTRAL IOWA WHERE DEW POINTS ARE IN
THE MID TO UPPER 50S AND TEMPERATURES ARE IN THE LOW 60S. 0-6KM
SHEAR IS ALSO WEAK AT 20-30KTS...SO ANY STORMS THAT HAVE
DEVELOPED ARE PULSEY AND COLLAPSE RATHER QUICKLY.
THE 21.00Z NAM/GFS/GEM/ECMWF AND 21.06Z RAP/HRRR/HOPWRF ARE ALL IN
VERY GOOD AGREEMENT WITH THE TIMING OF THE COLD FRONT COMING
THROUGH THE REGION TODAY. CURRENTLY...SURFACE OBS SHOW THAT THIS
FRONT IS IN WESTERN MINNESOTA/EASTERN NEBRASKA. GUIDANCE SUGGESTS
THAT THE FRONT WILL BE INTO NORTHEAST WISCONSIN/FAR SOUTHEAST
MINNESOTA/NORTHEAST IOWA AROUND NOON AND THEN CLEAR OF SOUTHWEST
WISCONSIN BY MID AFTERNOON. INSTABILITY WILL BUILD AHEAD OF THE
FRONT THOUGH THE 21.00Z NAM/GFS AND 21.06Z RAP LIKELY DEVELOP TOO
HIGH OF MUCAPE WITH THEM SHOWING SURFACE DEW POINTS CLIMBING UP TO
THE LOW 60S WHEN THEY WILL LIKELY BE MORE IN THE MID 50S. THERMAL
PROFILES SHOW THAT THIS INSTABILITY IS IN THE 0C TO -20C PORTION
OF THE SOUNDINGS...SO THERE COULD BE SOME SMALL HAIL THAT DEVELOPS
FROM THIS CONVECTION DESPITE 0-6KM SHEAR REMAINING WEAK AT
20-30KT.
ONCE THE FRONT COMES THROUGH...THERE IS A SOLID SLUG OF DRIER AIR
THAT WILL MOVE INTO THE REGION. TEMPERATURES MAY NOT MAKE TOO MUCH
OF AN INITIAL DROP SINCE THE FRONT IS COMING THROUGH DURING THE
MIDDLE OF THE DAY WITH THE DRIER AIR MASS BEHIND THE FRONT
ALLOWING FOR QUICKER WARMING UNDER SUNNY SKIES. TEMPERATURES WILL
PLUMMET TONIGHT WITH THE DRY AIR MASS IN PLACE AND NORTHWESTERLY
LOW LEVEL WINDS KICKING IN. COULD SEE SOME GUSTY WINDS AS WELL
WITH THIS DRY AIR IN THE AFTERNOON WITH SOME 35MPH GUSTS POSSIBLE
IN THE HIGHER TERRAIN OF SE MN/NE IA.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 323 AM CDT MON APR 21 2014
THE MAIN FOCUS IN THE EXTENDED IS ON A BROAD MID LEVEL TROUGH
CURRENTLY ALONG THE WEST COAST WHICH WILL PROPAGATE EAST ALONG THE
US/CANADIAN BORDER FROM THE MIDDLE TO END PORTION OF THE WEEK.
GUIDANCE HAS BEEN IN FAIRLY GOOD AGREEMENT ON THIS SYSTEM THOUGH
THERE ARE SOME MINOR DIFFERENCES THAT ARISE TOWARD THE LATER
PORTION OF THE SYSTEM. CONFIDENCE IS STILL FAIRLY HIGH THAT
PRECIPITATION WILL MOVE IN FROM THE WEST ON WEDNESDAY WITH THE
LEAD WARM AIR ADVECTION BAND FOLLOWED BY THE MAIN MOISTURE CHANNEL
AHEAD OF THE COLD FRONT ON THURSDAY. THERMAL PROFILES STILL DO NOT
SHOW MUCH IN THE WAY OF INSTABILITY BUT DO INCREASE PW VALUES UP
TO AROUND 1-1.50" EARLY ON THURSDAY. BASED ON THIS CONSISTENT
SIGNAL...HAVE UPPED PRECIPITATION CHANCES INTO THE 70-85 PERCENT
RANGE FOR MUCH OF THE REGION WITH TOTAL QPF VALUES EXPECTED TO BE
AROUND AN INCH.
GUIDANCE STARTS TO DEVIATE QUITE A BIT STARTING FRIDAY WITH THE
21.00Z GFS SHOWING A STRONG RIDGE OF HIGH PRESSURE EXTENDING FROM
HUDSON BAY THROUGH THE NORTHERN PLAINS WHILE THE 21.00Z ECMWF IS
WEAKER WITH THIS RIDGE AND KEEPS A LOW LEVEL THERMAL GRADIENT
ACROSS THE REGION ON INTO THE SOUTHERN GREAT LAKES. THE GFS
SOLUTION WOULD BE A COLDER/DRIER ONE FOR US WHILE THE ECMWF
SOLUTION WOULD MEAN A WETTER/SLIGHTLY WARMER SOLUTION THAT STILL
COULD BRING SOME P-TYPE ISSUES IN WITH IT. CURRENTLY...WPC IS
FAVORING THE GFS MORE THAN THE ECMWF BUT TIME WILL TELL. FOR
NOW...HAVE DONE A BLEND WITH SOME PRECIPITATION CHANCES IN THERE
FOR THE WEEKEND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1255 PM CDT MON APR 21 2014
A COLD FRONT WILL PUSH EAST OF THE TAF SITES THIS AFTERNOON AS
HIGH PRESSURE STARTS TO BUILD IN FROM THE NORTHERN PLAINS. A BKN
MVFR STRATUS DECK WILL SCATTER OUT AND EVENTUALLY CLEAR THIS
AFTERNOON AS DRIER AIR PUSHES IN FROM THE NORTHWEST. PLAN ON GUSTY
NORTHWEST WINDS OF 17 TO 20 KTS THIS AFTERNOON WITH GUSTS IN THE
25 TO 30 KT RANGE. THE WINDS WILL SUBSIDE INTO THE 7 TO 10 KT
RANGE LATE THIS EVENING. VFR CONDITIONS ARE EXPECTED FROM LATE
THIS AFTERNOON THROUGH THE OVERNIGHT HOURS INTO TUESDAY MORNING.
&&
.HYDROLOGY...
ISSUED AT 1255 PM CDT MON APR 21 2014
MINOR FLOODING CONTINUES ON THE MISSISSIPPI RIVER AT MCGREGOR.
ALONG THE MISSISSIPPI RIVER...RIVER LEVELS ARE EXPECTED TO
GRADUALLY FALL THROUGH MID WEEK BUT THEN WILL LEVEL OFF OR RISE
SLIGHTLY AS RUNNOFF FROM SNOWMELT OVER NORTHWEST WISCONSIN AND
CENTRAL INTO PORTIONS OF NORTHERN MINNESOTA MAKES ITS WAY INTO THE
LOCAL AREA. RIVER LEVELS ARE EXPECTED TO REMAIN ELEVATED INTO NEXT
WEEK.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...HALBACH
LONG TERM....HALBACH
AVIATION...WETENKAMP
HYDROLOGY....WETENKAMP
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1250 PM CDT MON APR 21 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 323 AM CDT MON APR 21 2014
THE MAIN FOCUS THROUGH TONIGHT IS ON THE TIMING OF THE COLD FRONT
PASSAGE AND THE CONVECTION THAT IS EXPECTED TO DEVELOP AHEAD OF IT
TODAY.
SHOWERS AND SOME THUNDERSTORMS CONTINUE ACROSS MUCH OF THE REGION
WHICH IS IN A BROAD CHANNEL OF LOW LEVEL MOISTURE TRANSPORT AHEAD
OF A SURFACE COLD FRONT. THE 21.07Z RAP ANALYSIS SHOWS THAT THE
HIGHEST 0-3KM MUCAPE OF A FEW HUNDRED J/KG IS ACROSS SOUTH
CENTRAL MINNESOTA AND NORTH CENTRAL IOWA WHERE DEW POINTS ARE IN
THE MID TO UPPER 50S AND TEMPERATURES ARE IN THE LOW 60S. 0-6KM
SHEAR IS ALSO WEAK AT 20-30KTS...SO ANY STORMS THAT HAVE
DEVELOPED ARE PULSEY AND COLLAPSE RATHER QUICKLY.
THE 21.00Z NAM/GFS/GEM/ECMWF AND 21.06Z RAP/HRRR/HOPWRF ARE ALL IN
VERY GOOD AGREEMENT WITH THE TIMING OF THE COLD FRONT COMING
THROUGH THE REGION TODAY. CURRENTLY...SURFACE OBS SHOW THAT THIS
FRONT IS IN WESTERN MINNESOTA/EASTERN NEBRASKA. GUIDANCE SUGGESTS
THAT THE FRONT WILL BE INTO NORTHEAST WISCONSIN/FAR SOUTHEAST
MINNESOTA/NORTHEAST IOWA AROUND NOON AND THEN CLEAR OF SOUTHWEST
WISCONSIN BY MID AFTERNOON. INSTABILITY WILL BUILD AHEAD OF THE
FRONT THOUGH THE 21.00Z NAM/GFS AND 21.06Z RAP LIKELY DEVELOP TOO
HIGH OF MUCAPE WITH THEM SHOWING SURFACE DEW POINTS CLIMBING UP TO
THE LOW 60S WHEN THEY WILL LIKELY BE MORE IN THE MID 50S. THERMAL
PROFILES SHOW THAT THIS INSTABILITY IS IN THE 0C TO -20C PORTION
OF THE SOUNDINGS...SO THERE COULD BE SOME SMALL HAIL THAT DEVELOPS
FROM THIS CONVECTION DESPITE 0-6KM SHEAR REMAINING WEAK AT
20-30KT.
ONCE THE FRONT COMES THROUGH...THERE IS A SOLID SLUG OF DRIER AIR
THAT WILL MOVE INTO THE REGION. TEMPERATURES MAY NOT MAKE TOO MUCH
OF AN INITIAL DROP SINCE THE FRONT IS COMING THROUGH DURING THE
MIDDLE OF THE DAY WITH THE DRIER AIR MASS BEHIND THE FRONT
ALLOWING FOR QUICKER WARMING UNDER SUNNY SKIES. TEMPERATURES WILL
PLUMMET TONIGHT WITH THE DRY AIR MASS IN PLACE AND NORTHWESTERLY
LOW LEVEL WINDS KICKING IN. COULD SEE SOME GUSTY WINDS AS WELL
WITH THIS DRY AIR IN THE AFTERNOON WITH SOME 35MPH GUSTS POSSIBLE
IN THE HIGHER TERRAIN OF SE MN/NE IA.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 323 AM CDT MON APR 21 2014
THE MAIN FOCUS IN THE EXTENDED IS ON A BROAD MID LEVEL TROUGH
CURRENTLY ALONG THE WEST COAST WHICH WILL PROPAGATE EAST ALONG THE
US/CANADIAN BORDER FROM THE MIDDLE TO END PORTION OF THE WEEK.
GUIDANCE HAS BEEN IN FAIRLY GOOD AGREEMENT ON THIS SYSTEM THOUGH
THERE ARE SOME MINOR DIFFERENCES THAT ARISE TOWARD THE LATER
PORTION OF THE SYSTEM. CONFIDENCE IS STILL FAIRLY HIGH THAT
PRECIPITATION WILL MOVE IN FROM THE WEST ON WEDNESDAY WITH THE
LEAD WARM AIR ADVECTION BAND FOLLOWED BY THE MAIN MOISTURE CHANNEL
AHEAD OF THE COLD FRONT ON THURSDAY. THERMAL PROFILES STILL DO NOT
SHOW MUCH IN THE WAY OF INSTABILITY BUT DO INCREASE PW VALUES UP
TO AROUND 1-1.50" EARLY ON THURSDAY. BASED ON THIS CONSISTENT
SIGNAL...HAVE UPPED PRECIPITATION CHANCES INTO THE 70-85 PERCENT
RANGE FOR MUCH OF THE REGION WITH TOTAL QPF VALUES EXPECTED TO BE
AROUND AN INCH.
GUIDANCE STARTS TO DEVIATE QUITE A BIT STARTING FRIDAY WITH THE
21.00Z GFS SHOWING A STRONG RIDGE OF HIGH PRESSURE EXTENDING FROM
HUDSON BAY THROUGH THE NORTHERN PLAINS WHILE THE 21.00Z ECMWF IS
WEAKER WITH THIS RIDGE AND KEEPS A LOW LEVEL THERMAL GRADIENT
ACROSS THE REGION ON INTO THE SOUTHERN GREAT LAKES. THE GFS
SOLUTION WOULD BE A COLDER/DRIER ONE FOR US WHILE THE ECMWF
SOLUTION WOULD MEAN A WETTER/SLIGHTLY WARMER SOLUTION THAT STILL
COULD BRING SOME P-TYPE ISSUES IN WITH IT. CURRENTLY...WPC IS
FAVORING THE GFS MORE THAN THE ECMWF BUT TIME WILL TELL. FOR
NOW...HAVE DONE A BLEND WITH SOME PRECIPITATION CHANCES IN THERE
FOR THE WEEKEND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1250 PM CDT MON APR 21 2014
A COLD FRONT WILL PUSH EAST OF THE TAF SITES THIS AFTERNOON AS
HIGH PRESSURE STARTS TO BUILD IN FROM THE NORTHERN PLAINS. A BKN
MVFR STRATUS DECK WILL SCATTER OUT AND EVENTUALLY CLEAR THIS
AFTERNOON AS DRIER AIR PUSHES IN FROM THE NORTHWEST. PLAN ON GUSTY
NORTHWEST WINDS OF 17 TO 20 KTS THIS AFTERNOON WITH GUSTS IN THE
25 TO 30 KT RANGE. THE WINDS WILL SUBSIDE INTO THE 7 TO 10 KT
RANGE LATE THIS EVENING. VFR CONDITIONS ARE EXPECTED FROM LATE
THIS AFTERNOON THROUGH THE OVERNIGHT HOURS INTO TUESDAY MORNING.
&&
.HYDROLOGY...
ISSUED AT 1250 PM CDT MON APR 21 2014
MINOR FLOODING CONTINUES ON THE MISSISSIPPI RIVER AT MCGREGOR.
ALONG THE MISSISSIPPI RIVER...RIVER LEVELS ARE EXPECTED TO
GRADUALLY FALL THROUGH MID WEEK BUT THEN WILL LEVEL OFF OR RISE
SLIGHTLY AS RUNNOFF FROM SNOWMELT OVER NORTHWEST WISCONSIN AND
CENTRAL INTO PORTIONS OF NORTHERN MINNESOTA MAKES ITS WAY INTO THE
LOCAL AREA. RIVER LEVELS ARE EXPECTED TO REMAIN ELEVATED INTO NEXT
WEEK.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...HALBACH
LONG TERM....HALBACH
AVIATION...WETENKAMP
HYDROLOGY....HALBACH