Area Forecast Discussion
Issued by NWS Hastings, NE

Home | Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS63 KGID 172017
AFDGID

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HASTINGS NE
317 PM CDT FRI APR 17 2015

...MORE BENEFICIAL RAINFALL AT TIMES THRU SAT NIGHT BUT WITH ONLY
LIMITED THREAT FOR SVR WX...

.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 317 PM CDT FRI APR 17 2015

ALOFT: THE MAIN BELT OF WESTERLIES WAS OVER SRN CANADA WITH A
CUT- OFF LOW SPINNING OVER CO. MULTIPLE PV ANOMALIES WERE ORBITING
THE LOW AND WILL COMBINE WITH DAYTIME HEATING TO MODULATE
SHWR/TSTM POTENTIAL THRU TOMORROW. THE LOW WILL REMAIN QUASI-
STATIONARY UNTIL TOMORROW. MEANWHILE...THE TROF MOVING INTO THE
PAC NW WILL BEGIN TO AMPLIFY AS IT CROSSES THE NRN ROCKIES
TOMORROW.

SURFACE: VERY LITTLE WILL CHANGE OVER THE NEXT 24 HRS. WEAK LOW
PRES WILL REMAIN ALONG THE KS/CO BORDER. THIS WILL MAINTAIN E-SE
LOW-LVL FLOW.

SAT IMAGERY SHOWS THE DRY SLOT HAS PROGRESSED THRU THE FCST AREA.
DAYTIME HEATING HAS BEEN LIMITED...ESPECIALLY N OF I-80. SO
INSTABILITY IS WEAK WITH MLCAPE UNDER 1000 J/KG...PRIMARILY OVER
THE S HALF OF THE FCST AREA. ISOLATED SHWRS/TSTMS COULD POP UP AT
ANY TIME...BUT NO SVR WX IS EXPECTED.

MORE ORGANIZED TSTMS WILL DEVELOP OVER WRN KS AND THE CLUES ARE
IN SAT IMAGERY. EXPECT AN ARC OF STORMS TO FORM AND LIFT N-NE INTO
THE FCST AREA. DEEP LAYER SHEAR IS MORE THAN SUFFICIENT AND COULD
COMPENSATE FOR MARGINAL INSTABILITY. THIS PROBABLY RESULTS IN SOME
SVR TSTMS OVER WRN KS AND THERE WILL BE A DECREASING WINDOW OF
OPPORTUNITY FOR THE SUBSEQUENT ARC OF STORMS TO PRODUCE SOME
MARGINAL SVR WX S OF A LINE FROM BEAVER CITY NE TO OSBORNE KS.

AFTER THAT...IT SHOULD BE SMALL HAIL...WIND GUSTS TO 45 MPH AT
WORST AND HVY RAIN. USED THE 06Z/12Z NAM TO TIME THE HIGHEST POPS
ACROSS THE FCST AREA AND THIS IS SUPPORTED BY THE ARW/NMM WRF.

HAVE INCLUDED AREAS OF FOG AFTER MIDNIGHT THRU MID-MORNING SAT.

BELIEVE MOST LOCATIONS WILL HAVE A SUBSTANTIAL BREAK AFTER THIS
ARC OF SHWRS/TSTMS MOVES THRU TONIGHT. EXPECT MOST OF TOMORROW
WILL BE DRY. THEN SCT SHWRS/TSTMS REDEVELOP SAT AFTERNOON. MLCAPE
IS NOT FCST TO EXCEED 1000 J/KG PER 15Z/SREF AND DEEP LAYER SHEAR
WILL BE AROUND 30 KTS. SPC HAS A SLGT RISK UP TO GRAND ISLAND
/GRI/. THIS WOULD BE PRIMARILY FOR A MARGINAL RISK OF 1" HAIL.


.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 317 PM CDT FRI APR 17 2015

SATURDAY NIGHT CONTINUES TO FAVOR WET WEATHER WITH RAIN AND
ISOLATED TSTMS WITH THE UPPER SYSTEM CROSSING THE PLAINS. THE COLD
FRONT AND UPPER TROUGH AXIS PASS TO THE EAST ON SUNDAY WITH PCPN
WINDING DOWN FROM WEST TO EAST. BEHIND THE COLD FRONT NORTH WINDS
WILL INCREASE ON SUNDAY AND MIXING DEEPENS TO JUST BELOW H7 WITH
WINDS AT THE TOP OF THE LAYER BETWEEN 30 AND 35KTS RESULTING IN
WINDY CONDITIONS THRU THE AFTN.

THE PLAINS LOW CONTINUES TO FILL ON SUNDAY AND EVENTUALLY PHASES
WITH A CANADIAN TROUGH TO OUR EAST. THE NORTHERN SYSTEM WILL BRING
A REINFORCING SHOT OF COOL AIR ON MONDAY...THEN HEIGHTS RISE
HEADING INTO THE MIDDLE OF THE WEEK AS A WESTERN RIDGE MIGRATES
EAST ONTO THE PLAINS AHEAD OF ANOTHER WESTERN CONUS TROUGH. CHCS
FOR PCPN RETURN INTERMITTENTLY AROUND THE MIDDLE OF THE WEEK IN
WAA AND AS A LEAD SHORTWAVE LIFTS OUT OF THE TROUGH IN THE WEST.
TOWARD THE END OF THE WEEK THE PATTERN IS TRENDING BLOCKY ACROSS
THE PLAINS IN BETWEEN TROUGHS FM THE WEST COAST TO THE
INTERMOUNTAIN WEST AND ACROSS THE NORTHEAST CONUS AND SOUTHERN
CANADIAN PROVINCES. THERE IS CONSIDERABLE MODEL UNCERTAINTY BY THE
END OF NEXT WEEK FOLLOWED THE ENSEMBLES IN THIS TIME FRAME.

&&

.AVIATION...(FOR THE 18Z KGRI/KEAR TAFS THROUGH 18Z SAT AFTERNOON)
ISSUED AT 101 PM CDT FRI APR 17 2015

THIS AFTERNOON: VARIABLE MOSTLY VFR CIGS...BUT TEMPORARY MVFR CIGS
AND MVFR/IFR SHWRS WILL BE POSSIBLE. SHWRS AND ISOLATED TSTMS
COULD DEVELOP AT ANY TIME...BUT THE BEST CHANCE WILL BE AFTER 21Z.
IT IS IMPOSSIBLE TO PROVIDE SPECIFIC TIMING FOR SHWRS/TSTMS SO
WATCH FOR AMENDMENTS...IF WE CAN GET A HANDLE ON SHORT-TERM
TRENDS. E WINDS 7-15 KTS. CONFIDENCE: MEDIUM

TONIGHT: VARIABLE MOSTLY VFR CIGS UNTIL 06Z. PROBABILITY FOR A
PERIOD OF IFR TSTMS IS HIGH...BUT PREFER TO NOT INCLUDE IN THE TAF
UNTIL WE ARE SURE THEY DEVELOP. LATEST SHORT-TERM GUIDANCE
SUGGESTS IFR FOG/STRATUS DEVELOP AFTER 06Z WITH DECREASING VSBYS/
CIGS ESPECIALLY AFTER 10Z. ESE WINDS LESS THAN 10 KTS. CONFIDENCE:
MEDIUM

SAT THRU 18Z: IFR FOG/STRATUS EVENTUALLY LIFTS TO VFR CU BY 18Z.
SE WINDS UNDER 10 KTS. CONFIDENCE: MEDIUM

&&

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

$$

SHORT TERM...HALBLAUB
LONG TERM...FAY
AVIATION...HALBLAUB



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