Area Forecast Discussion
Issued by NWS Marquette, MI

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
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 241913
AFDMQT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MARQUETTE MI
213 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 THROUGH MONDAY)
ISSUED AT 446 AM EST TUE FEB 24 2015

WITH AN OVERALL DIMINISHING TREND IN THE LES...WITH THE
MOVING/BREAKING ICE HAVING A SIGNIFICANT IMPACT ON WHAT WE AREA ABLE
TO GET IN OUR NW TO W FLOW THAT WILL REMAIN THROUGH FRIDAY. EXPECT A
FEW STREAMERS OF LES OFF OPEN AREAS...IMPACTING PRIMARILY ALGER AND
N LUCE COUNTIES.

THE MAIN STORY FOR THIS PERIOD WILL BE LOW TEMPS AND THE POTENTIAL
FOR NEAR ADVISORY WIND CHILLS AGAIN. INCLUDED IN THE HWO THE MENTION
OF WIND CHILL READINGS OF 20 BELOW TO NEAR 30 BELOW ZERO THROUGH MID
MORNING WEDNESDAY...AND AGAIN WEDNESDAY NIGHT INTO THURSDAY MORNING.
THE TIME OF NEAR CRITICAL WIND CHILL VALUES WILL LIKELY BE SHORTER
THURSDAY NIGHT INTO EARLY FRIDAY MORNING. MAY NOT HOIST WIND CHILL
ADVISORIES FOR THESE PERIODS OVER THE ENTIRE CWA AS WINDS MAY NOT
GET TO THE 10MPH OR GREATER THRESHOLD. GENERALLY WE HAVE BEEN TOO
STRINGENT ON THE WIND SIDE OF THE CRITERIA WHEN WIND CHILLS HAVE
BEEN GETTING CLOSER TO WARNING LEVELS.

KEPT WITH VERY COLD AIR SETTLING IN WEDNESDAY NIGHT/THURSDAY
MORNING...WITH THE TRADITIONAL COLD SPOTS FALLING -20 TO -25F. THE
LONGWAVE TROUGH IS BASICALLY OVERHEAD...AND 850MB TEMPS -23 TO
-25C...AND THE SFC RIDGE EXPANDING ACROSS THE UPPER GREAT LAKES FROM
CENTRAL CANADA AND THE N PLAINS STATES.

OFFSHORE WINDS FRIDAY THROUGH SATURDAY SHOULD RESULT IN DRY WEATHER
FOR ALL OF UPPER MI. OPTED FOR A MODEL BLEND FOR SATURDAY NIGHT
THROUGH THE REST OF THE PERIOD...ONCE AGAIN LIMITED THE LES
POTENTIAL TO CHANCE AT MOST GIVEN THE ICE COVER OVER MUCH OF LAKE
SUPERIOR. THE SNOW POTENTIAL IS BECOMING LESS IMPRESSIVE
SUNDAY...WITH MUCH OF THE MOISTURE UNABLE TO RISE MUCH FARTHER N
THAN S WI.

AS NOTED FROM PREVIOUS LONG TERM DISCUSSION... FEBRUARY 2015 IS A
LOCK TO BREAK LAST YEAR/S RECORD COLD FEBRUARY. THROUGH THE
22ND...THE AVERAGE TEMP THIS MONTH HAS BEEN 2.9 DEGREES. PERFORMING
A ROUGH CALCULATION BASED OFF THE FORECAST DATA...WE SHOULD END UP
RIGHT AROUND 2.5 DEGREES FOR THE AVERAGE TEMPERATURE THIS MONTH AT
NWS MARQUETTE. THAT WOULD BEAT THE RECORD OF 5.6 DEGREES SET JUST
LAST YEAR. AT OTHER SITES WITH LONGER PERIODS OF RECORD...THIS
FEBRUARY WILL LIKELY END UP AS A TOP 5 OR TOP 10 COLDEST FEBRUARY.
MANY SITES HAVE 1936 AS THE COLDEST FEBRUARY ON RECORD...WHICH AT
IRONWOOD EVEN ENDED UP WITH AN AVERAGE TEMPERATURE BELOW ZERO
(ALMOST 4 DEGREES COLDER THAN WHAT HAS OCCURRED THIS MONTH).
&&

.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...KF
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.