Area Forecast Discussion
Issued by NWS Hastings, NE

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FXUS63 KGID 201732
AFDGID

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HASTINGS NE
1232 PM CDT SUN APR 20 2014

.UPDATE...
ISSUED AT 1147 AM CDT SUN APR 20 2014

THE 00Z NAM 4KM WRF-ARW HAS THE BEST HANDLE ON WHAT HAS EVOLVED
THIS MORNING...IE VERY LITTLE. THE BATCH OF LIGHT RAIN LIFTING N
FROM N-CNTRL KS INTO S-CNTRL NEB IS DISSIPATING.MEANWHILE...
ECHOES ARE BEGINNING TO INCREASE FROM LEXINGTON-ORD-SANDHILLS.
A CHECK OF FCST REFLECTIVITY COMING IN FROM THE NEW 12Z NAM 4KM
HAS TOO MUCH COVERAGE COMPARED TO REALITY.

STILL EXPECT SCATTERED TSTMS TO DEVELOP...MAINLY S OF I-80 AND
ESPECIALLY S OF HWY 6. CONVECTIVE TEMP IS ABOUT 71F AND WE ARE
CLOSE NOW. SO CU SHOULD BEGIN DEVELOPING SHORTLY...ESPECIALLY WITH
MORE SUNSHINE THAN EXPECTED 24 HRS AGO. HOWEVER...PATCHES OF MID-
LVL CLOUDS MOVING THRU WILL HINDER INITIAL DEVELOPMENT.

RAP/HRRR MLCAPE WILL REMAIN BELOW 1000 J/KG. GIVEN THE NEARLY
MOIST ADIABATIC LAPSE RATES ON THE 12Z DDC SOUNDING AND DEEP LAYER
SHEAR LESS THAN 15 KTS...DO NOT ENVISION ANY STRONG STORMS
DEVELOPING. SO THE HWO WILL BE UPDATED SHORTLY TO REMOVE THAT
WORDING.

STORMS THAT DEVELOP WILL TEND TO MOVE TOWARD THE NE.

PRECIPITABLE WATER WILL INCREASE TO ABOUT 1" AND THIS IS 2
STANDARD DEVIATIONS ABOVE NORMAL. SO SOME DECENT RAIN IS
POSSIBLE...BUT IT WILL BE EXTREMELY LOCALIZED GIVEN THE SHORT
DURATION OF ANY STORMS THAT DEVELOP.


UPDATE ISSUED AT 825 AM CDT SUN APR 20 2014

SEND AN ENHANCED SHORT-TERM FCST UPDATE. THE 13Z FCST TEMPS
STARTED TOO SHARP OF A CLIMB COMPARED TO OBS. SO THEY WERE TRIMMED
BACK. THE OTHER MAJOR CHANGE WAS TO LOAD THE CONSENSUS OF THE HI-
RES SHORT-TERM MODELS FOR DEWPOINTS THRU 00Z. DEWPOINTS IN THE 30S
HAVE CREPT INTO THE FAR NW FRINGE OF THE FCST AREA /SEE OBS AT
ORD-BROKEN BOW-N PLATTE/. SHORT-TERM MODELING HAS A GOOD HANDLE ON
THIS.

&&

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 444 AM CDT SUN APR 20 2014

MAP ANALYSIS INDICATES AN UPPER TROPOSPHERIC CLOSED LOW OVER THE
SOUTHEASTERN CONUS...ANOTHER OVER SOUTH CENTRAL CANADA...AND AN
UPPER TROPOSPHERIC SHORT WAVE OVER PORTIONS OF NEW MEXICO AND
COLORADO. ENHANCED UPPER TROPOSPHERIC JET ENERGY IS NOTED EXTENDING
ALONG TWO BRANCHES ACROSS THE CONUS...WITH ONE BRANCH ACROSS THE
SOUTHERN CONUS AND GULF OF MEXICO...AND ANOTHER EXTENDING FROM THE
NORTHWESTERN CONUS INTO THE NORTHERN PLAINS AND EVENTUALLY THE
NORTHEASTERN CONUS. UPPER TROPOSPHERIC FLOW OVER OUR AREA REMAINS
FAIRLY WEAK...ONLY MAXING OUT AT AROUND 50KTS NEAR 35000FT AGL PER
00Z SOUNDING DATA FROM KLBF AND KOAX. WATER VAPOR IMAGERY INDICATES
INCREASED UPPER TROPOSPHERIC MOISTURE EXTENDING FROM THE SOUTHERN
PLAINS INTO PORTIONS OF THE CENTRAL PLAINS...WITH THIS INCREASED
MOISTURE HELPING PROMOTE INCREASED CLOUD COVER OVER MUCH OF OUR AREA
THIS MORNING. AT THE SURFACE A STATIONARY BOUNDARY IS NOTED ACROSS
NEBRASKA...KANSAS AND EASTERN COLORADO. AS OF 08Z THIS BOUNDARY WAS
NOTED FROM NEAR KBVN...TO NEAR KEAR...TO NEAR KHLC. THE RESULTANT
LOWER TROPOSPHERIC WIND FIELD ACROSS OUR AREA REMAINS FROM THE SOUTH
ACROSS ROUGHLY THE SOUTHEASTERN ONE-HALF OF OUR CWA...WITH MORE OF A
NORTH/NORTHEASTERLY LOWER TROPOSPHERIC WIND FIELD NOTED AT LOCATIONS
FARTHER NORTHWEST ACROSS THE AREA.

GUIDANCE FROM THE NAM...OPERATIONAL GFS...EC AND SREF-MEAN ALL
SUGGEST THE UPPER TROPOSPHERIC SHORT WAVE OVER THE SOUTHWESTERN
CONUS WILL MOVE EAST/NORTHEAST THROUGH THE NEXT 24 HOURS...MOVING
INTO THE SOUTHERN PLAIN BY 00Z MONDAY AND INTO THE MID-MISSISSIPPI
VALLEY BY 12Z MONDAY. AS THIS UPPER TROPOSPHERIC SHORT WAVE MOVES
INTO PORTIONS OF THE PLAINS AND MISSISSIPPI VALLEY...AND AREA OF LOW
BAROMETRIC PRESSURE AT THE SURFACE IS EXPECTED TO DEVELOP OVER
PORTIONS OF THE MID-MISSISSIPPI VALLEY TONIGHT. SO ALTHOUGH THE
LOWER TROPOSPHERIC BAROCLINIC ZONE SHOULD CONTINUE MEANDERING ACROSS
OUR AREA THROUGH THE DAY TODAY...THE DEVELOPMENT OF THE SURFACE LOW
ACROSS THE MISSISSIPPI VALLEY SHOULD HELP PUSH THE BAROCLINIC ZONE
THROUGH OUR CWA FROM NORTHWEST TO SOUTHEAST TONIGHT...WITH THIS
BAROCLINIC ZONE EXPECTED TO HAVE PRETTY MUCH CLEARED OUR AREA TO THE
SOUTHEAST BY 12Z MONDAY.

UPPER TROPOSPHERIC THERMAL ADVECTION...AHEAD OF THE SOUTHWESTERN
CONUS SHORT WAVE...IS INCREASING ACROSS OUR AREA AND AS A
RESULT...WEAK SHOWER ACTIVITY HAS BEEN TRYING TO MATERIALIZE OVER
WESTERN AND NORTHERN PORTIONS OF OUR CWA THROUGH MUCH OF THE NIGHT.
AS THE SHORT WAVE ADVANCES EAST/NORTHEAST AND UPPER TROPOSPHERIC
THERMAL ADVECTION CONTINUES TO INCREASE ACROSS THE REGION...IT
STANDS TO REASON THAT CHANCES FOR  WILL ALSO LIKELY INCREASE
THROUGH THE DAY. THIS IS A SOLUTION SUPPORTED BY QPF FIELDS FROM
THE NAM...OPERATIONAL GFS...EC AND SREF-MEAN. IN ADDITION TO THE
SYNOPTIC-SCALE OMEGA PROVIDED BY THE UPPER TROPOSPHERIC SHORT
WAVE...LOWER TROPOSPHERIC CONVERGENCE AND LIFT ALONG THE
BAROCLINIC ZONE WILL ALSO LIKELY AID IN CONVECTIVE DEVELOPMENT
THIS AFTERNOON INTO THIS EVENING. GIVEN ALL THIS...WENT AHEAD WITH
POPS ACROSS MOST ALL OF THE CWA FOR TODAY. CHANCES FOR
PRECIPITATION WILL ALSO PERSIST INTO THE OVERNIGHT
HOURS...ALTHOUGH GUIDANCE SUGGESTS THE PRIMARY AXIS OF UPPER
TROPOSPHERIC THERMAL ADVECTION WILL MOVE MORE INTO THE MISSISSIPPI
VALLEY BY 06Z...AND WITH THE LOWER TROPOSPHERIC BAROCLINIC ZONE
CLEARING OUR AREA TO THE SOUTHEAST...IT SEEMS REASONABLE TO ASSUME
CHANCES FOR PRECIPITATION WILL BEGIN TO DIMINISH ACROSS THE AREA
AS WE HEAD INTO EARLY MONDAY MORNING.

THE NAM AND OPERATIONAL GFS BOTH SUGGEST 0-1KM MLCAPE VALUES OF
~500J/KG WILL BE REALIZED ACROSS MUCH OF THE AREA TODAY...ALTHOUGH
THE GFS DOES HINT AT VALUES PERHAPS APPROACHING 1000J/KG ACROSS OUR
NORTH THIS AFTERNOON. VERY LITTLE IF ANY DEEP LAYER BULK SHEAR WILL
EXIST OVER THE AREA DUE TO THE AFOREMENTIONED LACK IN UPPER
TROPOSPHERIC JET ENERGY. GIVEN ALL THIS...IT SEEMS UNLIKELY
CONVECTION WILL PROMOTE SEVERE HAIL OR WIND GUSTS TODAY...BUT WILL
GO AHEAD AND CONTINUE A MENTION OF SUB-SEVERE HAIL IN THE HWO IN
CASE THE GFS VERIFIES THE SLIGHTLY HIGHER FORECAST OF POTENTIAL
INSTABILITY ACROSS PORTIONS OF THE AREA.

IT APPEARS THE LOWER TROPOSPHERIC AIR MASS FOR TODAY WILL CHANGE
VERY LITTLE WHEN COMPARED TO YESTERDAY...BUT WITH INCREASED CLOUD
COVER AND POSSIBLE PRECIPITATION...A SOMEWHAT COOLER DAY IS STILL
EXPECTED FOR MOST LOCATIONS TODAY. GUIDANCE SUGGESTS AFTERNOON
TEMPERATURE READINGS IN THE 70S WILL BE OBSERVED ACROSS MUCH OF THE
AREA AND THIS SEEMS REASONABLE. ALTHOUGH WEAK LOWER TROPOSPHERIC
COLD AIR ADVECTION WILL BEGIN WORKING INTO THE AREA LATER
TONIGHT...INCREASED CLOUD COVER AND POSSIBLE PRECIPITATION WILL
LIKELY KEEP TEMPERATURE READINGS PRETTY CLOSE TO WHERE THEY ARE
EARLY THIS MORNING. WENT AHEAD WITH OVERNIGHT LOWS IN THE 50S FOR
THE MOST PART FOR TONIGHT AS A RESULT.

.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 444 AM CDT SUN APR 20 2014

WITH THE WEEKEND WEATHER SYSTEM FADING INTO THE REARVIEW MIRROR
VERY EARLY IN THIS 6-DAY PERIOD...THE MAIN FORECAST FOCUS WILL
INCREASINGLY TURN TO THE MID-WEEK SYSTEM THAT STILL LOOKS TO EXERT
ITS INFLUENCE ON THE LOCAL AREA MAINLY DURING THE TUESDAY NIGHT-
THURSDAY TIME FRAME...AND ESPECIALLY WEDNESDAY/WEDNESDAY NIGHT
WHEN THE POTENTIAL...KEY WORD POTENTIAL...STILL EXISTS FOR A ROUND
OF SEVERE THUNDERSTORMS. HOWEVER...DESPITE THIS POTENTIAL SEVERE
WEATHER THREAT GETTING A LITTLE CLOSER IN TIME AND THE OFFICIAL
SPC DAY 4 OUTLOOK HIGHLIGHTING NEARLY THE ENTIRE CWA...WANT TO
AGAIN CAUTION THAT THERE ARE A TON OF DETAILS TO WORK OUT BEFORE
THIS IS A SLAM-DUNK SEVERE EVENT...AS IF ANYTHING THE LATEST 00Z
DETERMINISTIC RUNS OF THE 00Z ECMWF/GFS/GEM ARE A LITTLE MORE OUT
OF SYNC WITH EACH OTHER THAN 24 HOURS AGO ESPECIALLY REGARDING
SURFACE FRONT POSITIONS AND INSTABILITY MAGNITUDE...AND AT LEAST
FOR NOW THE GFS/GEM PAINT A SOMEWHAT MORE FAVORABLE SEVERE STORM
SETUP FOR THE LOCAL AREA AND THE ECMWF SOMEWHAT LESS-SO. ALONG
THOSE SAME LINES...THE GFS/GEM SOLUTION STILL SHOWS A FAVORABLE
SETUP FOR ADVISORY-LEVEL SOUTHERLY WINDS ON WEDNESDAY...WHILE THE
ECMWF IS A BIT FASTER PUSHING THE COLD FRONT INTO THE AREA AND
THUS DOWNPLAYS THE VERY STRONG SOUTH WIND POTENTIAL. AT LEAST FOR
NOW...THE OFFICIAL FORECAST CONTINUES LEANING TOWARD THE WINDIER
SOLUTION...AND WILL CONTINUE THIS MENTION IN THE HAZARDOUS WEATHER
OUTLOOK (HWO). LOOKING BEYOND THE MID-WEEK SYSTEM...HAVE
MAINTAINED SOME SLIGHT POPS FOR THE VERY END OF THE PERIOD ON
SATURDAY FOR THE NEXT IN THE SERIES OF LOW PRESSURE SYSTEMS...BUT
CURRENT INDICATIONS SUGGEST THAT THE BULK OF PRECIP POTENTIAL WITH
THIS ONE WOULD HOLD OFF UNTIL MORE-SO THE SAT NIGHT-SUNDAY TIME
FRAME...OR JUST BEYOND THE SCOPE OF THE OFFICIAL 7-DAY. ALTHOUGH
IT IS FAR...FAR TOO SOON TO FOCUS ON THIS SYSTEM...THE GENERAL
SYNOPTIC PATTERN AND TIME OF YEAR AGAIN SUGGESTS SOME SEVERE
POTENTIAL COULD EXIST FOR LATE NEXT WEEKEND.

BRIEFLY TOUCHING ON MONDAY AFTERNOON FIRE DANGER POTENTIAL...WILL
CONTINUE A MENTION OF NEAR-CRITICAL FIRE DANGER...AS MUCH OF THE
CWA IS STILL FORECAST TO OBSERVE RELATIVE HUMIDITY VALUES DROP
DOWN TO AROUND 22-26 PERCENT IN THE PRESENCE OF NORTHERLY WINDS
GUSTING GENERALLY 20-25 MPH. OF COURSE...WITH THE POTENTIAL FOR
PARTS OF THE AREA TO RECEIVE AT LEAST MODEST RAINFALL BEFORE
THEN...ANY NEAR-CRITICAL FIRE THREAT COULD BE LARGELY MITIGATED
ANYWAY. NO MATTER...DO NOT FORESEE FIRE PARAMETERS DROPPING INTO
ACTUAL CRITICAL RANGE AND THUS REQUIRING A HEADLINE.

NOW GETTING INTO THE DETAILS AND TAKING IT IN 24-48 HOUR
BLOCKS...

MONDAY DAYTIME/MONDAY NIGHT...THE VAST MAJORITY OF THIS 24 HOURS
SHOULD BE DRY FOR THE MAJORITY OF THE CWA. THE ONLY POSSIBLE
EXCEPTION LOOKS TO BE MAINLY WITHIN THE SOUTHEAST 1/4 OF THE CWA
RIGHT AWAY ON MONDAY MORNING...AND SIMILAR TO THE PREVIOUS
FORECAST HAVE LINGERED ONLY A SLIGHT 20 POP WITHIN THIS AREA TO
COVER THE POSSIBLE LAST DEPARTING SHOWERS ASSOCIATED WITH THE
CURRENT LOW PRESSURE SYSTEM. ONLY HAVE THIS POP IN PLACE THROUGH
10AM/15Z...WHICH FITS WELL WITH THE SIMULATED REFLECTIVITY FROM
THE 00Z 4KM WRF-NMM...ALTHOUGH ITS WORTH NOTING THAT THE NEW 06Z
NAM TRIES TO HOLD ON A LITTLE LONGER CLOSER TO NOON IN KS ZONES.
ALSO KEPT OUT ANY THUNDER MENTION WITH THIS POST-SUNRISE PRECIP
POTENTIAL...ALTHOUGH SUPPOSE ITS NOT OUT OF THE QUESTION THAT A
ROGUE RUMBLE OR TWO COULD STILL LINGER IN THIS AREA...AND WILL
DEFER TO NEXT FEW SHIFTS TO DECIDE IF ITS WORTHY OF A FORMAL
INCLUSION. AT ANY RATE...ONCE THIS MONDAY MORNING ACTIVITY FINALLY
VACATES...THE REMAINDER OF THE DAY/NIGHT CARRIES A HIGH CONFIDENCE
OF REMAINING DRY AS THE CENTER OF THE SLOW-MOVING MID LEVEL
SHORTWAVE TROUGH THAT BEGINS THE DAY OVER EASTERN KS STEADILY
PUSHES OFF TO THE EAST...ALLOWING A BROAD...EXPANSIVE MID/UPPER
RIDGE AXIS TO OVERSPREAD THE CENTRAL PLAINS BY MONDAY NIGHT. AT
THE SURFACE...PRESSURE RISES PUSHING IN FROM THE NORTHWEST WILL
PROMOTE A SOMEWHAT BREEZY NORTH WIND THROUGH MUCH OF THE DAY WITH
SUSTAINED SPEEDS GENERALLY 16-23 MPH WITH GUSTS 25 TO SLIGHTLY
OVER 30 MPH...ALTHOUGH THESE SPEEDS WERE TEMPERED SLIGHTLY FROM
PREVIOUS FORECAST. THESE BREEZES WILL BE ON THE DECLINE BY LATE
AFTERNOON...AND FAIRLY LIGHT SPEEDS GENERALLY AROUND 8 MPH OR LESS
WILL PREVAIL THROUGH MOST OF THE NIGHT AS A PASSING SURFACE RIDGE
AXIS GRADUALLY CHANGES DIRECTION FROM NORTHERLY TO MORE EAST-
SOUTHEASTERLY. TEMP-WISE...ASSUMING THAT PLENTY OF SUN WORKS IN
BEHIND THE DEPARTING MORNING CLOUDS/POSSIBLE PRECIP...NUDGED UP
HIGHS A FEW DEGREES MAINLY IN THE SOUTHEAST...AIMING FOR A RANGE
FROM NEAR-70 NORTHWEST TO MID 70S SOUTHEAST. AS ALREADY COVERED
ABOVE...THESE MILD TEMPS COULD TEAM WITH MUCH DRIER DEWPOINTS IN
THE 30S TO ENHANCE FIRE DANGER SOMEWHAT. AS FOR MONDAY NIGHT LOW
TEMPS...AND AGAIN ASSUMING NO WORSE THAN MOSTLY CLEAR
SKIES...SHOULD SEE A DECENT DROP INTO THE LOW 40S MOST
AREAS...WITH COLDER UPPER 30S MOST FAVORED IN THE USUAL DAWSON TO
VALLEY/GREELEY CORRIDOR IN THE NORTHWEST.

TUESDAY/TUESDAY NIGHT...THE TRANSITION BACK TO MORE ACTIVE WEATHER
STARTS TO GET UNDERWAY BY TUESDAY NIGHT...BUT CONFIDENCE REMAINS
HIGH IN A DRY DAY. IN THE MID-UPPER LEVELS...THE GENERAL SYNOPTIC
PICTURE PER THE 00Z ECMWF/GFS INDICATES THAT THE HEART OF THE
BROAD RIDGE AXIS WILL PASS OVER THE LOCAL AREA DURING THE
DAY...WHILE THE LEADING EDGES OF SOUTHWESTERLY FLOW ALOFT
DOWNSTREAM FROM THE MAIN LARGE-SCALE TROUGH CENTERED OVER THE
NORTHWEST QUADRANT OF THE CONUS WILL MOVE INTO THE CENTRAL PLAINS
TUESDAY NIGHT. PRECIP-WISE...ANY AFTERNOON THUNDERSTORM THREAT
SHOULD REMAIN GENERALLY 100+ MILES WEST OF THE CWA OVER THE
CENTRAL HIGH PLAINS SO THE DAY IS DRY. THEN TUESDAY NIGHT...A VERY
STRONG LOW LEVEL JET EVIDENT AT 850MB CRANKS UP OVER THE
AREA...TRANSPORTING AT LEAST LIMITED MOISTURE. NEEDLESS TO
SAY...AM NOT REALLY EXPECTING ANY KIND OF SEVERE WEATHER THREAT
WITH ANY STORMS THAT MIGHT DEVELOP TUESDAY NIGHT ALONG THE EASTERN
PERIPHERY OF THIS LOW LEVEL JET...AS THE NAM ONLY ADVERTISES CAPE
IN THE 850-700MB LAYER UP TO MAYBE 300-400 J/KG. POP-WISE...HAVE
ONLY SLIGHT 20S EVERYWHERE BEFORE MIDNIGHT...WITH 30S THEN PAINTED
IN EASTERN ZONES LATE IN THE NIGHT. EVEN SO...SOME MODELS SUGGEST
THAT MUCH OF THIS NOCTURNAL ACTIVITY COULD LARGELY FOCUS EAST
THROUGH NORTH OF THE CWA...AND NOT NECESSARILY AFFECT THE LOCAL
AREA...THUS THE FAIRLY LOW POPS FOR NOW. AT THE SURFACE THROUGH
THIS PERIOD...BREEZY SOUTHEAST WINDS WILL BECOME ESTABLISHED AS
SURFACE PRESSURE FALLS CRANK UP ALONG A HIGH PLAINS LEE
TROUGH...WITH SUSTAINED SPEEDS DURING MOST OF THE DAY RANGING FROM
AROUND 15 MPH IN THE FAR EASTERN CWA TO AROUND 25 MPH IN THE FAR
WEST. WITH CONTINUED BREEZY CONDITIONS THROUGH THE NIGHT...LOW
TEMPS SHOULD HOLD UP WELL INTO THE 50S MOST AREAS. DURING THE
DAY...MADE VERY LITTLE CHANGE TO HIGHS WITH LOW-MID 70S MOST
AREAS.

WEDNESDAY/WEDNESDAY NIGHT...THE OPENING LONG TERM PARAGRAPH ABOVE
ALREADY TOUCHED ON SOME OF THE ISSUES REGARDING SEVERE
WEATHER/STRONG WIND POTENTIAL. ON THE BASIC MID- UPPER PATTERN
HOWEVER...A RATHER STRONG AND POTENTIALLY SLIGHTLY NEGATIVELY
TILTED SHORTWAVE TROUGH WILL SWING INTO THE CENTRAL CONUS IN SOME
WAY...SHAPE OR FORM. AT THE SURFACE...THE LATEST ECMWF BRINGS A
COLD FRONT ACROSS THE CWA MUCH EARLIER IN THE DAY THAN THE GFS
SOLUTION...WHICH SHARPENS A FAIRLY STOUT NORTH-SOUTH DRYLINE
THROUGH WESTERN KS/SOUTHWEST NEB JUST TO THE NORTHEAST OF A
ROUGHLY 992MB SURFACE LOW ALONG THE KS/CO BORDER LATE IN THE DAY.
ONE BIG QUESTION REGARDING THE MAGNITUDE OF THE CONVECTIVE THREAT
INVOLVES WHETHER THERE WILL BE DAYTIME CONVECTION AROUND THAT
COULD INHIBIT AFTERNOON DESTABILIZATION...OR WHETHER THERE MIGHT
BE ONE MAIN SURFACE-BASED SHOW IN THE AFTERNOON/EVENING FIRING
ALONG THE DRYLINE/COLD FRONT AND MOVING EAST. FOR SURE...DEEP
LAYER SHEAR ON THE ORDER OF 40+KT WOULD BE SUFFICIENT FOR
SUPERCELLS IF OTHER FACTORS COME TOGETHER. NUDGED UP DAYTIME POPS
TO 40 PERCENT IN MOST AREAS...BUT MAINTAINED THE HIGHEST 50-60
POPS OF THE ENTIRE LONG TERM FORECAST TO WEDNESDAY NIGHT AS THE
MAIN LARGE-SCALE TROUGH MOVES THROUGH...POTENTIALLY RESULTING IN
CONVECTION MORPHING INTO A LARGER COMPLEX. ALSO AS ALREADY TOUCHED
ON EARLIER...THE GFS SOLUTION WOULD STRONGLY SUPPORT ADVISORY
LEVEL SOUTH WINDS AHEAD OF THE DEEPENING SURFACE LOW...SO THIS
COULD BE AN ISSUE NO MATTER HOW HIGH OR LOW THE SEVERE THREAT ENDS
UP BEING. TEMPS ARE OBVIOUSLY SOMEWHAT OF A QUESTION GIVEN PRECIP
POTENTIAL...BUT CHANGED HIGHS LITTLE WITH MAINLY UPPER 70S-LOW
80S.

THURSDAY DAYTIME THROUGH FRIDAY NIGHT...KEPT THE MAJORITY OF THIS
48-HOUR TIME FRAME VOID OF POPS...EXCEPT FOR A LINGERING SLIGHT
CHANCE OF SHOWERS ON THURSDAY IN THE WAKE OF THE DEPARTING
MID/UPPER LOW THAT WILL BE SWINGING INTO THE UPPER MIDWEST/GREAT
LAKES. AT THE SURFACE...THURSDAY IS LIKELY TO BE A BIT BREEZY OUT
OF THE WEST-NORTHWEST...WITH LIGHTER WINDS ON FRIDAY AS A RIDGE
AXIS PASSES THROUGH UNDER A BRIEF PERIOD OF SHORTWAVE RIDGING
ALOFT. ALREADY BY FRIDAY NIGHT THE ECMWF BRINGS IN THE NEXT
POTENTIAL ROUND OF SHOWERS/STORMS MAINLY INTO NORTHERN ZONES...BUT
DID NOT BITE ON THIS QUITE YET. TEMPS ON BOTH DAYS WERE CHANGED
VERY LITTLE...WITH HIGHS ON BOTH DAYS MAINLY 65-70.

SATURDAY DAYTIME...MAINTAINED 20 POPS FOR SHOWERS/STORMS FROM
PREVIOUS FORECAST AS THE LEAD SHORTWAVE ENERGY ASSOCIATED WITH THE
NEXT LARGE SCALE WESTERN CONUS TROUGH ENTERS THE AREA.
HOWEVER...AS EARLIER TOUCHED ON...ITS VERY POSSIBLE IF NOT LIKELY
THAT BETTER SHOWER/STORM CHANCES WILL HOLD OFF UNTIL LATER IN THE
WEEKEND. HIGH TEMPS PRELIMINARY AIMED MAYBE A LITTLE ON THE COOL
SIDE WITH MAINLY LOW-MID 60S FOR NOW.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1232 PM CDT SUN APR 20 2014

THIS AFTERNOON: VFR MID-LEVEL CIGS...BUT THERE IS A VERY LOW
PROBABILITY OF A TEMPORARY MVFR SHWR/TSTM. AT THIS TIME THE RISK
IS TO LOW TO INCLUDE IN THE TAF...BUT WATCH FOR POSSIBLE
AMENDMENTS. WINDS WILL AVERAGE SW AROUND 10 KTS. CONFIDENCE:
MEDIUM

TONIGHT: QUITE A BIT OF MULTI-LAYERED VFR CLOUD DEBRIS WILL BE
LEFT AROUND FROM SCT SHWRS/TSTMS. A WEAK COOL FRONTAL PASSAGE WILL
MOVE THROUGH IN THE 08-10Z TIME FRAME...WITH A WSHFT TO NW.
CLEARING BEHIND THE FRONT. CONFIDENCE: MEDIUM

MON THRU 18Z: VFR AND BASICALLY SKC. NW WINDS WILL BECOME N...
INCREASE AND GUST UP TO 25 KTS. CONFIDENCE: HIGH

&&

.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&

$$

UPDATE...HALBLAUB
SHORT TERM...BRYANT
LONG TERM...PFANNKUCH
AVIATION...HALBLAUB



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