Area Forecast Discussion
Issued by NWS Marquette, MI

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 KMQT 242108
AFDMQT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MARQUETTE MI
408 PM EST TUE FEB 24 2015

.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 212 PM EST TUE FEB 24 2015

UPPER AIR PATTERN CONSISTS OF A CLOSED 500 MB LOW OVER THE DESERT
SW...UPPER TROUGHING OVER THE UPPER GREAT LAKES WITH A SHORTWAVE
ALONG THE MANITOBA/ONTARIO BRODER. THIS SHORTWAVE WILL BE
ACCOMPANIED BY COLDER AIR AS IT MOVES THROUGH THE AREA THIS
AFTERNOON. THE UPPER TROUGH THEN REMAINS OVER THE UPPER GREAT LAKES
FOR THE REST OF THIS FORECAST PERIOD.

DID NOT MAKE TOO MANY CHANGES TO THE GOING FORECAST FOR TEMPERATURES
OR WEATHER. BIG QUESTION IS HOW THE ICE IS GOING TO AFFECT THE LAKE
EFFECT SNOW AND WHAT THE EFFECT OF THE WIND WILL BE ON THE ICE
COVERAGE. CONFIDENCE IS FAIRLY LOW THAT THE MODELS ARE PICKING UP ON
THE ICE COVERAGE AND MIGHT BE OVERDOING THE QPF AMOUNTS AND POPS A
BIT. DECIDED BEST THING TO DO IS KEEP THE CURRENT FORECAST GOING AND
GO WITH PERSISTENCE FOR THIS FORECAST AS COLD AIR COMES IN. AS FOR
WIND CHILLS...WINDS STAY UNDER 10 MPH FOR TONIGHT AND WILL NOT GO
WITH A WIND CHILL ADVISORY FOR THIS REASON.

.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 407 PM EST TUE FEB 24 2015

COLD AND GENERALLY QUIET CONDITIONS ARE EXPECTED THROUGH THE START
OF THE WEEKEND...AS A ARCTIC HIGH PRESSURE MOVES FROM SOUTHERN
SASKATCHEWAN THROUGH THE DAKOTAS AND INTO THE MID MISSISSIPPI
VALLEY AND EVENTUALLY THE LOWER GREAT LAKES BY SATURDAY. THIS WILL
KEEP THE UPPER GREAT LAKES REGION UNDER A SURFACE RIDGE AND
GENERALLY LIGHT NORTHWEST TO NORTH-NORTHWEST WINDS TO START THE
PERIOD BEFORE BACKING TO THE WEST THURSDAY NIGHT AND EVENTUALLY
SOUTHWEST BY SATURDAY. WITH THE COLD AIR IN PLACE (850MB TEMPS
AROUND -23C) AND REINFORCED BY A SHORTWAVE MOVING THROUGH WEDNESDAY
NIGHT...THE POTENTIAL FOR LAKE EFFECT IS THERE.
UNFORTUNATELY...CONFIDENCE IS LOW DUE TO THE UNCERTAINTY ON THE
LOCATIONS OF GAPS IN THE ICE. LOOKING AT VISIBLE SATELLITE OVER
WESTERN LAKE SUPERIOR TODAY...DECENT AREAS OF OPEN WATER ARE PRESENT
OFF THE MINNESOTA ARROWHEAD AND ALSO TO THE EAST OF THE APOSTLE
ISLANDS DUE TO THE STRONG WINDS OVER THE LAST 24 HOURS. THAT
INCREASES THE CONFIDENCE FOR LAKE EFFECT FOR PORTIONS OF WESTERN
UPPER MICHIGAN (MAINLY GOGEBIC/ONTONAGON COUNTIES).
ELSEWHERE...CLOUDS WERE OBSCURING THE ABILITY TO SEE THE ICE COVER
OVER CENTRAL/EASTERN LAKE SUPERIOR AND WILL MAKE SOME ASSUMPTIONS.
THINK AREAS EAST/SOUTH OF THE KEWEENAW PENINSULA SHOULD HAVE OPENED
UP BASED OFF SATELLITE YESTERDAY EVENING...SO WILL FOCUS THE HIGHEST
POPS IN THE AREAS DOWNSTREAM OF THAT. THAT WOULD GENERALLY AFFECT
ALGER COUNTY WEDNESDAY NIGHT INTO THURSDAY BEFORE WINDS START TO
BACK AND PUSH THE LAKE EFFECT TOWARDS FAR NORTHERN LUCE COUNTY
THURSDAY NIGHT BEFORE EXITING BY FRIDAY EVENING (ALTHOUGH THE
STRENGTH WILL DIMINISH WITH 850MB TEMPS WARMING TOWARDS -17C). WILL
KEEP SNOW ACCUMULATIONS LIGHT WITH INVERSION HEIGHTS GENERALLY
STAYING BELOW 5KFT AND THE CLOUD LAYER STAYING ABOVE THE DGZ AND
PRODUCING SMALL FLAKES. ONE FINAL NOTE WITH THE LAKE EFFECT...MODELS
CONTINUE TO INDICATE WINDS TURNING A LITTLE MORE NORTHERLY ON
WEDNESDAY NIGHT...SO WILL HAVE THE POPS SHIFT MORE INTO THE
NORTHERLY WIND AREAS (IRONWOOD AND MARQUETTE COUNTY) DURING THAT
TIME. FOR THE WEEKEND...THERE ARE STILL SOME HINTS OF SHORTWAVE
ENERGY EJECTING OUT OF AN UPPER TROUGH OVER THE SOUTHWESTERN CONUS
AND ASSISTED BY A NORTHERN STREAM SHORTWAVE MOVING THROUGH
ONTARIO...POTENTIALLY PRODUCING LIGHT SNOW OVER THE AREA DURING THE
SAT NIGHT TO SUN NIGHT PERIOD. DETERMINISTIC MODELS AND THEIR
ENSEMBLE MEMBERS ARE SHOWING A WIDE VARIETY OF SOLUTIONS...LARGELY
JUST BRUSHING THE SOUTHERN AREAS OF THE UPPER GREAT LAKES
REGION...SO WILL CONTINUE TO JUST HAVE SLIGHT/CHANCE POPS FOR THAT
TIME FRAME. HIGH PRESSURE WILL BUILD BACK INTO THE AREA AT THE START
OF THE WEEK AND LEAD TO A DRY START OF THE NEXT WORK WEEK.

AS FOR TEMPERATURES...WEDNESDAY NIGHT HAS THE POTENTIAL TO SEE
SIGNIFICANT VARIATIONS DEPENDING ON THE WHERE THE LAKE EFFECT
CLOUDS ARE. WHERE CLOUDS OCCUR...TEMPS WILL LIKELY BE IN THE SINGLE
DIGITS BELOW ZERO...WHILE OUTSIDE OF THOSE AREAS...EXPECT LOWS TO
FALL INTO THE TEENS TO 20S BELOW ZERO UNDER LIGHT WINDS. IN
ADDITION...THINK THERE WILL BE HIGH CLOUDS BRUSHING THE SOUTHERN
PART OF THE CWA FROM THE DISTURBANCE MOVING ACROSS SOUTHERN
WISCONSIN. THAT MAY HOLD OFF THE DROP FOR SOME OF THE INTERIOR
LOCATIONS INITIALLY. WHILE WINDS WILL BE ON THE LIGHT SIDE...DID
CONTINUE TO MENTION LOWER WIND CHILLS IN THE HWO. AS TEMPERATURES
ALOFT SLOWLY MODERATE THROUGH THE REST OF THE WORK WEEK AND INTO THE
WEEKEND...HAVE SHOWN TEMPERATURES SLOWLY RISING TO THE 20S BY
SUNDAY.
&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1214 PM EST TUE FEB 24 2015

A REINFORCING DISTURBANCE AND ATTENDANT ARCTIC COLD FRONT WILL BRING
MORE SHSN/GUSTY NW WINDS/BLSN IN THE AFTERNOON IN THE PRESENCE OF
DIURNAL HEATING AND CAA THAT SHARPEN LOW LEVEL LAPSE RATES. ALTHOUGH
EXTENSIVE ICE COVER WL LIMIT THE INTENSITY OF THE LES...THE BLSN AT
THE MORE EXPOSED CMX LOCATION WILL LIKELY RESULT IN IFR VSBYS AT
LEAST PART OF THE TIME UNTIL THE EVNG...WHEN LARGER SCALE STRONG
SUBSIDENCE IN THE WAKE OF THIS DISTURBANCE SUPPRESSES THE LES OVER
THE ENTIRE AREA. CONDITIONS AT SAW WILL STAY MVFR FOR THE PERIOD
AND IWD WILL GO FROM MVFR TO VFR THIS EVENING AS DRIER AIR MOVES IN.
&&

.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 212 PM EST TUE FEB 24 2015

A HIGH PRESSURE RIDGE WILL BUILD BACK INTO THE AREA WEDNESDAY AND
REMAIN INTO SUNDAY...LEADING TO GENERALLY LIGHT WINDS BELOW 20KTS.
ICE COVER IS EXTENSIVE...SO FREEZING SPRAY IS NOT A PROBLEM.
&&

.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&

$$

SHORT TERM...07
LONG TERM...SRF
AVIATION...07
MARINE...07



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