Area Forecast Discussion
Issued by NWS Rapid City, SD

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 KUNR 291718
AFDUNR

AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NATIONAL WEATHER SERVICE RAPID CITY SD
1118 AM MDT FRI APR 29 2016

.SHORT TERM...TODAY THROUGH SATURDAY NIGHT
ISSUED AT 242 AM MDT FRI APR 29 2016

LARGE UPPER TROUGH COVERS THE WESTERN CONUS AND INCLUDES TWO
CLOSED LOWS...ONE OVER WESTERN MT AND THE OTHER NEAR THE FOUR
CORNERS REGION. UPPER HIGH PRESSURE IS PUSHING INTO THE NORTHERN
PLAINS FROM CANADA. MID TO LOW CLOUDS COVER THE CWA...WITH SOME
FOG REPORTED OVER THE SOUTHERN HILLS. RADAR SHOWS SOME LIGHT
SHOWERS OVER THE WESTERN SD PLAINS...AND KPHP HAS RECENTLY
REPORTED RAIN. WINDS ARE CALM TO LIGHT AND VARIABLE...WITH TEMPS
IN THE 30S.

BASE OF TROUGH SWINGS NORTHEASTWARD OVER THE CENTRAL ROCKIES TODAY
AS UPPER LOW DEEPENS. GENERALLY MODELS HAVE TRENDED SOUTH WITH
THIS SYSTEM...WITH RAIN/SNOW LIKELY NOT MOVING INTO SOUTHERN SD
UNTIL TONIGHT AND NORTHWESTERN SD REMAINING DRY. CUT BACK POPS
ACCORDINGLY. HOWEVER...AMPLE MOISTURE AND SOME WEAK INSTABILITY
MAY ALLOW LIGHT SHOWERS TO CONTINUE ACROSS PORTIONS OF THE AREA
TODAY. UNDER CLOUDY SKIES...HIGHS TODAY WILL BE IN THE 40S TO
LOWER 50S...WITH SOME 30S IN THE BLACK HILLS.

AS THE 700MB LOW SHIFTS OVER NE/KS...PRECIP WILL PUSH NORTHWARD INTO
THE AREA. MODELS ARE IN GOOD AGREEMENT ON SOUTHERN SD RECEIVING THE
MOST PRECIP AND NORTHERN SD REMAINING DRY. GFS AND ECM HAVE A LITTLE
FARTHER NORTH EXTENT OF PRECIP THAN THE NAM AND GEM.
HOWEVER...MODELS DISAGREE ON SNOW POTENTIAL WITH THIS SYSTEM. MAIN
AREAS OF CONCERN ARE THE BLACK HILLS AND SOUTHERN SD...WHERE
NAM/SREF SHOW 8+ INCHES OF SNOW BY 18Z SAT...WHILE ECM/GFS SHOW A
COUPLE INCHES IN THE HILLS AND UP TO 6 INCHES FOR SOUTHERN SD.
CURRENTLY HAVE 3-5 INCHES OF SNOW IN THE FORECAST FOR THE BLACK
HILLS...WITH A COUPLE INCHES OVER SOUTHERN SD. CONSIDERED ISSUING AN
ADVISORY FOR THE HILLS. HOWEVER...WITH MODELS TRENDING FARTHER SOUTH
AND THE DIFFERENCE IN MODEL SNOWFALL SOLUTIONS...WILL HOLD OFF FOR
NOW.

LOW PRESSURE SYSTEM SLIDES EASTWARD ON SATURDAY WHILE HIGH PRESSURE
PUSHES IN FROM THE NORTH. RAIN/SNOW WILL GRADUALLY END FROM NORTH TO
SOUTH SATURDAY NIGHT. OVERALL SOUTHERN SD COULD SEE AROUND AN INCH
OF QPF BY SUNDAY MORNING. GUSTY NORTHEAST WINDS ON THE NORTHERN SIDE
OF THE LOW WILL AFFECT THE REGION SATURDAY AFTERNOON AND
EVENING...ESPECIALLY ACROSS SOUTH CENTRAL SD. HIGHS WILL RANGE FROM
NEAR 40 ACROSS SOUTHERN SD AND THE BLACK HILLS TO THE LOWER 50S
ACROSS NORTH CENTRAL SD.

.LONG TERM...SUNDAY THROUGH THURSDAY
ISSUED AT 242 AM MDT FRI APR 29 2016

UPPER LOW SHIFTS AWAY FROM THE AREA SUNDAY AS DRIER AIR
FILTERS INTO THE REGION. WITH SOME MUCH NEEDED SUNSHINE...HIGH WILL
REACH THE 50S ON THE PLAINS. UPPER RIDGE BUILDS ACROSS THE NORTHERN
ROCKIES/PLAINS BY MID WEEK...THEN REMAINS OVER THE AREA INTO THE
WEEKEND. THIS WILL RESULT IN DRY WEATHER AND ABOVE AVERAGE
TEMPERATURES.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY)
ISSUED AT 1114 AM MDT FRI APR 29 2016

WDSPRD MVFR AND LOCALIZED IFR CIGS WILL PERSIST THROUGH THE
AFTN...WITH FAR NWRN SD AND PARTS OF NERN WY REMAINING VFR. WDSPRD
RAIN/SNOW EXPECTED TO MOVE NORTHWARD FROM NEB INTO NERN WY AND
WRN SD THIS EVE AND OVERNIGHT...ESPECIALLY ALONG AND SOUTH OF I90.
THIS WILL BRING WDSPRD IFR CONDITIONS...AND LOCALIZED LIFR
CONDITIONS IN THE HIGHER TERRAIN. FAR NWRN SD LIKELY TO REMAIN
MVFR OR VFR.

&&

.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&

$$

SHORT TERM...POJORLIE
LONG TERM...7
AVIATION...JOHNSON


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