626
FXUS63 KFSD 202320 AAA
AFDFSD
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE SIOUX FALLS SD
520 PM CST THU FEB 20 2020
SHORT TERM
(THIS EVENING THROUGH FRIDAY)
ISSUED AT 328 PM CST THU FEB 20 2020
TONIGHT: WINDS WILL REMAIN ON THE BREEZY SIDE INTO THE EVENING
HOURS, BUT WILL DECREASE AS A STRONG SURFACE INVERSION SETS UP
DECOUPLING US FROM THE WINDS ALOFT. TEMPERATURES WILL REMAIN FAIRLY
CONSTANT THROUGHOUT THE NIGHT, AS RADIATIONAL COOLING BATTLES
AGAINST THE WARM AIR BEING ADVECTED INTO THE REGION.
FRIDAY: AS THE SURFACE HIGH PRESSURE CASUALLY SLIDES SOUTHWARDS, THE
PRESSURE GRADIENT WILL TIGHTEN AND THE AFOREMENTIONED INVERSION WILL
GIVE WAY LATER IN THE MORNING ALLOWING WINDS TO INCREASE. DUE TO THE
SOUTHERLY WINDS, WARM AIR WILL CONTINUE TO ADVECT INTO THE AREA
LEADING TO ABOVE NORMAL TEMPERATURES. THANKS TO THE STRONG SUNSHINE
ON THURSDAY AND ABOVE FREEZING TEMPERATURES ON FRIDAY, THE SNOW PACK
IS NOT IDEAL FOR BLOWING SNOW...BUT PATCHY BLOWING SNOW REMAINS A
POSSIBILITY LARGELY ALONG THE BUFFALO RIDGE IN SW MN.
LONG TERM
(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 328 PM CST THU FEB 20 2020
FRIDAY NIGHT: DUE TO THE MELTING SNOW THAT IS EXPECTED DURING THE
DAY, PATCHY FOG MAY DEVELOP FRIDAY NIGHT ALONG A LINE FROM YANKTON,
SD TO SPENCER, IA. WINDS AND SOME MID-LEVEL CLOUDS WILL LARGELY
LIMIT HOW MUCH FOG DEVELOPS, BUT IF THE WINDS BECOME CALMER THAN
CURRENTLY EXPECTED THERE WILL LIKELY BE MORE FOG.
SATURDAY: ANOTHER QUIET DAY IS IN STORE FOR SATURDAY, WITH SOME
CLOUDS HANGING AROUND IN THE MORNING HOURS THANKS TO AN UPPER LEVEL
DISTURBANCE MOVING THROUGH. AREAS ALONG THE MISSOURI RIVER COULD
SEE TEMPERATURES REACH 50, WITH AREAS AS FAR NORTH AS HURON AND
MARSHALL POSSIBLY SEEING 40. SIMILAR TO FRIDAY NIGHT, MELTING SNOW
COULD LEAD TO ANOTHER PATCHY FOGGY NIGHT AS WINDS ARE QUITE
LIGHT.
SUNDAY: A CALM DAY WITH ABOVE AVERAGE TEMPERATURES INTO THE EARLY
AFTERNOON, BUT CLOUD COVERAGE WILL BE INCREASING THROUGHOUT THE DAY.
MODELS HAVE BEEN PERSISTENT IN PRODUCING A COLORADO LOW WITH THE
CENTER OF THE CIRCULATION FORECAST TO SKIRT SOUTH AND EAST OF OUR
AREA, POSSIBLY BRINGING LIGHT WINTRY PRECIPITATION TO THE
SURROUNDING SIOUX CITY AREA AND OUT TOWARDS STORM LAKE INTO THE
OVERNIGHT HOURS.
MONDAY-THURSDAY: MODELS CONTINUE TO DISAGREE ON HOW TO HANDLE THE
LONGER RANGE PATTERN FOR NEXT WEEK. GFS REMAINS THE MODEL THAT
PRODUCES THE MOST PRECIPITATION, WITH THE GEM AND ECMWF GIVING US
LESS. DUE TO THE UNCERTAINTY, LEFT POPS AT A CHANCE MONDAY INTO
WEDNESDAY MORNING. ONE THING THAT THE MODELS DO AGREE ON IS THAT
TEMPERATURES WILL DROP BACK DOWN BELOW NORMAL TEMPERATURES LATER
IN THE WEEK.
AVIATION
(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING)
ISSUED AT 516 PM CST THU FEB 20 2020
EXPECT VFR CONDITIONS TO PREVAIL THROUGH THE PERIOD. SOUTH WINDS
AT OR BELOW 10 KTS ARE EXPECTED OVERNIGHT AT THE SURFACE, BUT LOW
LEVEL WIND SHEAR DEVELOPS LATE TONIGHT WITH A SOUTHWESTERLY LOW
LEVEL JET. EXPECT WINDS TO BECOME MORE SOUTHWESTERLY AND
EVENTUALLY WESTERLY ON FRIDAY WITH GUSTY WINDS UP TO 30 KTS
DEVELOPING FOR LATE MORNING THROUGH THE AFTERNOON, STRONGEST IN
NORTHWEST IA AND SOUTHWEST MN.
FSD WATCHES/WARNINGS/ADVISORIES
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
SHORT TERM...TRELLINGER
LONG TERM...TRELLINGER
AVIATION...BP
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page