Area Forecast Discussion
Issued by NWS Hastings, NE

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
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 280839
AFDGID

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HASTINGS NE
339 AM CDT MON JUL 28 2014

.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 337 AM CDT MON JUL 28 2014

BIGGEST CHALLENGE WILL BE DETERMINING RISK OF PRECIPITATION AND
THUNDER LATE TONIGHT.

A HIGHLY AMPLIFIED REX BLOCK HAS ITS AXIS OVER THE ROCKIES AS A DEEP
TROUGH IS ANCHORED OVER THE EASTERN UNITED STATES. WE WILL CONTINUE
TO LIE UNDERNEATH NORTHWEST FLOW. A SURFACE HIGH IS HELPING TO KEEP
DEW POINTS NOTICEABLY LOWER. JUDGING ON RECENT NUMERICAL MODEL
PERFORMANCE...I WENT CLOSER TO THE ECMWF HI RES BIAS CORRECTED FOR
HIGHS TODAY AND NAM12BC. ANOTHER DRY DAY IS IN STORE...BUT TONIGHT
COULD BE A BIT DIFFERENT. MOST NUMERICAL MODELS ARE PLACING AT LEAST
SOME PRECIPITATION OVER OUR CWA AFTER MIDNIGHT DUE TO SOME MID-LEVEL
ISENTROPIC LIFT. PRECIPITATION IS MORE LIKELY IN OUR SOUTHWEST...BUT
EVEN OUR NORTHEAST COULD GET IN ON SOME SPRINKLES. THUNDER IS
UNLIKELY...BUT THERE COULD BE JUST ENOUGH INSTABILITY TO GET SOME
THUNDER IN OUR SOUTHWESTERN CWA. HIGH TEMPERATURES ARE A BIT LOWER
THAN THE PREVIOUS FORECAST. WITH THE ADDITIONAL SKY COVER...I DID
RAISE LOWS A TAD COMPARED TO THE PREVIOUS FORECAST.

.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 337 AM CDT MON JUL 28 2014

ALOFT: OVER THE PAST 30 DAYS THE MEAN PATTERN HAS BEEN A WRN USA
RIDGE/ERN USA TROF. THE MULTI-DAY MEAN 500 MB HEIGHTS FROM THE EC/
GEM/GFS ENSEMBLE MEANS AGREE THIS PATTERN WILL BE MAINTAINED THRU
NEXT SUN. THE LAST 3 GFS/EC/GEM/UKMET RUNS ARE ON BOARD AS WELL. SO
NW FLOW WILL CONT WITH VERY LITTLE OR NO DYNAMIC FORCING.

EFFECTS ON TEMPS/PRECIP: THIS WEEK WILL BE COOLER THAN NORMAL WITH
BELOW TO MUCH BELOW NORMAL RAINFALL.

SEVERAL WEAK/SUBTLE PERTURBATIONS /SOME CONVECTIVELY GENERATED/ WILL
ORBIT THE SUBTROPICAL HIGH OVER THE DESERT SW THIS WEEK. THIS
COMBINED WITH HEATING OF THE ELEVATED TERRAIN TO THE W...
CONVERGENCE ALONG THE FRONT AND UPSLOPE FLOW WILL RESULT IN DAILY
TSTM ACTIVITY W-SW OF THE FCST AREA WITH SEVERAL CYCLES OF MCS
ACTIVITY. MODEL QPF CLUSTERING CONTS TO SUGGEST THIS MCS ACTIVITY
WILL TRACK PRIMARILY FROM CO SE INTO WRN/SRN KS AND OK.

SURFACE: THE PRIMARY POLAR FRONT WILL FAR S OF ITS USUAL SUMMER
POSITION THIS WEEK...QUASI-STATIONARY FROM THE GULF COAST STATES
BACK TO TX AND THEN BANKED UP AGAINST THE FRONT RANGE OF THE
ROCKIES. HIGH PRES WILL REMAIN PARKED OVER THE NRN PLAINS.

HAZARDS:


THE DAILY DETAILS...

TUE: TOUGH TO GET A GOOD READ BUT IT`S LOOKING M/CLOUDY. SCATTERED
SHWRS/SPRINKLES? MAY BE ON-GOING AT DAWN AS REMNANTS FROM OVERNIGHT
ACTIVITY LINGER. GFS/EC/NAM/GEM ALL FCST FRONTOGENESIS IN THE 850-
700 MB LAYER TO WEAKEN AND MID-LVL SUBSIDENCE TO SETTLE IN. THIS
SHOULD CHOKE OFF THE SHWR ACTIVITY. I MAY HAVE OVERPLAYED THE
THUNDER IN A VERY MARGINAL SITUATION. SOUNDINGS SUGGEST SOME OF THIS
ACTIVITY MAY NOT BE TALL ENOUGH FOR MUCH ICE IN-CLOUD. CONFIDENCE IS
BELOW AVERAGE ON HIGHS TEMPS DUE TO VARIABLE CLOUD COVER.

WED: TEMPS PROBABLY COOLEST OVER N-CNTRL KS. ANOTHER M/CLOUDY DAY.
TSTM CLUSTERS WILL BE ON-GOING FORENOON JUST SW OF THE FCST AREA.
MOST OF THE REGION WILL SEE SUBSTANTIAL CIRRUS CLOUD COVER...
ESPECIALLY IN THE MORNING. THERE IS AN OUTSIDE CHANCE THE NRN FRINGE
OF SOME OF THIS ACTIVITY COULD GRAZE N-CNTRL KS OR EXTREME S-CNTRL
NEB. CONFIDENCE IS BELOW AVERAGE ON HIGHS TEMPS DUE TO UNCERTAINTY
ON CLOUD COVER.

AT 50-50 BLEND OF THE 15Z/21Z SREF POPS GAVE ME 40-50% N AND W OF
THE TRI-CITIES IN THE AFTERNOON. THE NAM AND SREF ARE ON THEIR OWN
WITH THIS POTENTIAL. OF THE GLOBAL MODELS...ONLY YESTERDAY`S 12Z/GEM
SUGGESTS POSSIBLE THUNDER. AFTER COORDINATION WITH LBF/OAX...THESE
POPS WERE REMOVED.

THU-SUN: CURRENTLY LOOKING DRY AND VERY COMFORTABLE WITH TSTM
ACTIVITY REMAINING FAR TO THE W AND S.

ONCE WE GET BEYOND 10 DAYS /AUG 5/ THE EC/GFS/CFSV2 ENSEMBLE MEANS
SUGGEST A POSSIBLE PATTERN CHANGE WITH A TROF FCST TO DEVELOP IN THE
W. THIS WILL INCREASE THE ODDS IN GETTING BENEFICIAL RAINS. WE WILL
CONT TO MONITOR THIS POTENTIAL.

JULY: CLOSING OUT THIS MONTH WITH A COOL SPELL GUARANTEES THIS JULY
WILL GO DOWN AS COOLER THAN NORMAL. WE SAW A SUBSTANTIAL TURN-AROUND
FROM THE VERY WET JUNE. ONLY A COUPLE NARROW SWATHS WERE FORTUNATE
ENOUGH TO GET NORMAL RAINFALL. MUCH OF THE FCST AREA WAS DRIER THAN
NORMAL...BARELY RECEIVING 50% OF NORMAL.

&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1256 AM CDT MON JUL 28 2014

VFR CONDITIONS ARE EXPECTED AS HIGH PRESSURE CONTINUES TO
DOMINATE. SOME ISENTROPIC LIFT COULD CAUSE SOME INCREASE OF MID-
LEVEL CLOUDINESS TOWARD THE VERY END OF THE FORECAST...BUT ANY
PRECIPITATION SHOULD HOLD OFF UNTIL AFTER THE VALID TIME OF THE
FORECAST.

&&

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

$$

SHORT TERM...HEINLEIN
LONG TERM...HALBLAUB
AVIATION...HEINLEIN



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