933
FXUS63 KDLH 231745
AFDDLH
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DULUTH MN
1145 AM CST SUN FEB 23 2020
SHORT TERM
(TODAY THROUGH MONDAY)
ISSUED AT 304 AM CST SUN FEB 23 2020
EARLY MORNING WATER VAPOR IMAGERY SHOWING ZONAL FLOW PREVAILING
ACROSS THE NORTHERN U.S., WITH A DEEP UPPER TROUGH SLOWLY
TRANSITIONS ACROSS THE FOUR CORNERS REGION. CLOSER TO OUR AREA,
SHORTWAVE ENERGY IS SEEN THIS MORNING OVER CENTRAL NORTH DAKOTA,
WHICH WITH TIME, WILL LEAD TO AN INCREASE IN CLOUDS AND A TREAT
FOR LIGHT SNOW SHOWER ACTIVITY ACROSS PORTIONS OF OUR AREA EARLY
THIS AFTERNOON. BEFORE THIS, THE GOES-EAST CHANNEL DIFFERENCE FOG
PRODUCT IS SHOWING LOW STRATUS AND PATCHY FOG ACROSS PORTIONS OF
THE REGION THIS MORNING, WITH THE MOST CONCENTRATED ACTIVITY NOTED
EAST OF THE I-35 CORRIDOR. DEGREE OF EXPANSION REMAINS IN
QUESTION THIS MORNING AS SOUTHWEST FLOW OF 4-8 KTS ACROSS THE
REMAINING PORTION OF NORTHEAST MINNESOTA MAY CREATE ENOUGH MIXING
TO PREVENT FOG FROM BECOMING MORE WIDESPREAD. FOR NOW, HAVE
MAINTAINED A FOG MENTION FOR MANY AREAS THIS MORNING, BUT WILL
MAKE ADJUSTMENTS AS NEEDED AS TRENDS BECOMING MORE FIRMLY
ESTABLISHED.
SHIFTING GEARS TO LATER TODAY, FCST MODELS ARE IN EXCELLENT
AGREEMENT THAT THE BEST FORCING FOR THE AFOREMENTIONED SHORTWAVE
WILL REMAIN NORTH OF THE INTERNATIONAL BORDER AS IT SLIDES EAST
WITH TIME. THAT SAID, THIS FEATURE WILL BE ACCOMPANIED BY A COLD
FRONT WHICH COMBINED WITH THE MODEST UPPER FORCING, MAY BE ENOUGH
TO SQUEEZE OUT A LITTLE SNOW SHOWER ACTIVITY ACROSS THE BORDERLAND
AREA LATER TODAY, HOWEVER NO ACCUMULATION IS EXPECTED AT AT THIS
TIME. DESPITE THE INCREASING CLOUDS, WARM AIR ADVECTION AND BREEZY
SOUTHWEST WINDS OF 10-20 MPH WILL ALLOW TEMPERATURES TO AGAIN
CLIMB INTO THE MIDDLE TO UPPER 30S ACROSS MUCH OF THE AREA, WITH
LOW 40S POSSIBLE ACROSS PORTIONS OF NORTHWEST WISCONSIN. DRY
WEATHER WILL THEN CONTINUE INTO MONDAY WITH TEMPERATURES EXPECTED
TO WARM INTO THE LOWER TO MIDDLE 30S FOR DAYTIME HIGHS.
LONG TERM
(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 304 AM CST SUN FEB 23 2020
THE UPPER LEVEL PATTERN EARLY NEXT WEEK SHOWS AN INTERESTING PHASING
OF A NORTHERN AND SOUTHERN STREAM LOW PRESSURE SYSTEM, ONE OVER THE
NORTHWEST CONUS, WITH ANOTHER SLOWER MOVING ONE OVER EASTERN CO/NM.
THESE BEGIN TO PHASE TOGETHER AS THE FASTER NORTHERN STREAM FEATURE
MOVES ACROSS THE NORTHERN ROCKIES ON MONDAY, AND BY TUESDAY MORNING
THE SOUTHERN FEATURE IS A WAVE EJECTING OUT OF THE EAST SIDE OF A
STRONG UPPER LOW OVER NEBRASKA. THE SURFACE LOWS OVER EASTERN MT
AND ANOTHER OVER EASTERN OK MONDAY MORNING MORPH INTO A STRONGER
SURFACE LOW OVER THE MID MISSISSIPPI RIVER VALLEY, WITH A STRONG
INVERTED TROUGH EXTENDING TOWARD SOUTH DAKOTA. THE BULK OF THESE
SYSTEMS REMAIN SOUTH OF THE FORECAST AREA, AND WE SHOULD REMAIN
DRY MONDAY NIGHT. HOWEVER, WE WILL HAVE FAIRLY STRONG NORTHEAST
FLOW OVER THE FORECAST AREA, AND BY TUESDAY WE WILL HAVE SOME LAKE
EFFECTS GOING ON, AND WHILE I DON'T THINK WE WILL HAVE ENOUGH
LAKE SURFACE T TO 850MB T DIFFERENCE TO PRODUCE LAKE EFFECT SNOW,
I DO EXPECT STRATUS AND EITHER FLURRIES/DRIZZLE TO DEVELOP ALONG
THE SOUTH SHORE LATE MONDAY NIGHT, GRADUALLY INCREASING ON
TUESDAY. A SECONDARY UPPER LEVEL TROUGH AXIS MOVING ACROSS THE
AREA ON TUESDAY NIGHT AND WEDNESDAY ALONG WITH COLDER AIR MOVING
IN ALOFT SHOULD INCREASE OUR PRECIPITATION CHANCES, AND WITH THE
NORTH-NORTHEAST LOW LEVEL FLOW CONTINUING, LAKE EFFECT SNOW
CHANCES INCREASE AS WELL. THE MODELS DO NOT HAVE VERY GOOD
AGREEMENT ON HOW QUICKLY THIS SYSTEM PULLS OFF TO THE EAST, BUT
SNOW CHANCES SHOULD TAPER OFF EITHER WEDNESDAY NIGHT OR THURSDAY.
EARLIER IN THE WEEK THE MILDER TEMPERATURES SHOULD CONTINUE WITH
HIGHS IN THE 20S AND LOWER 30S, AND OVERNIGHT LOWS IN THE SINGLE
DIGITS AND TEENS. ONCE THIS UPPER LEVEL SYSTEM MOVES OFF TO OUR
EAST, A POOL OF COLDER AIR MOVES OVER THE AREA FOR THE LATER
PORTIONS OF THE WORK WEEK, BRINGING ANOTHER PERIOD OF COLDER
TEMPERATURES WHICH THEN MODERATE THROUGH NEXT WEEKEND. FOR NOW I
HAVE HIGHS IN THE 20S FOR THURSDAY AND FRIDAY WITH LOWS IN THE
SINGLE DIGITS, BUT WOULD NOT BE SURPRISED TO NEED TO LOWER THESE
AS WE GET CLOSER INTO THIS TIME RANGE. TEMPERATURES SHOULD
MODERATE BACK INTO THE LOWER TO MID 30S FOR HIGHS FOR NEXT
WEEKEND.
AVIATION
(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1145 AM CST SUN FEB 23 2020
A PATCH OF LOW STRATUS BETWEEN 1500-2100 FEET WAS MOVING TOWARDS
INL AND BRD AT THE START OF THE FORECAST. VFR ELSEWHERE. LOOK FOR
THESE LOW CLOUDS WITH MVFR CIGS TO REACH HIB EARLY THIS AFTERNOON
AND PERSIST TO THE EARLY EVENING BEFORE MOVING EAST OF
INL/BRD/HIB. NOT EXPECTING THESE LOWER CIGS TO AFFECT DLH OR HYR.
GUSTY SURFACE WINDS UNTIL SUNSET. AFTER SUNSET, SOME BR IS
EXPECTED TO FORM NEAR BRD WITH CIGS AND VSBYS INTO THE IFR RANGE
FROM 08-12Z. CIGS WILL IMPROVE AT BRD TO MVFR BY 15Z AND VFR BY
16Z. ELSEWHERE, VFR CONDITIONS ARE EXPECTED.
PRELIMINARY POINT TEMPS/POPS
DLH 38 19 33 22 / 10 0 0 20
INL 36 16 32 17 / 20 10 0 10
BRD 39 16 33 22 / 0 0 0 10
HYR 42 17 37 22 / 0 0 0 0
ASX 42 20 35 23 / 0 0 0 20
DLH WATCHES/WARNINGS/ADVISORIES
WI...NONE.
MN...NONE.
LS...NONE.
UPDATE...LE
SHORT TERM...CG
LONG TERM...LE
AVIATION...GSF
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page