Area Forecast Discussion
Issued by NWS Grand Rapids, MI

Home | Current Version | Previous Version | Graphics & Text | 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 KGRR 271923
AFDGRR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
323 PM EDT WED MAY 27 2015

LATEST UPDATE...
SYNOPSIS/SHORT TERM/LONG TERM/MARINE

.SYNOPSIS...
ISSUED AT 323 PM EDT WED MAY 27 2015

RAIN CHANCES WILL DIMINISH BEGINNING THIS EVENING. ANOTHER ROUND OF
SHOWERS AND THUNDERSTORMS IS EXPECTED FRIDAY INTO SATURDAY. THIS
WILL BE FOLLOWED BY DRIER AND MUCH COOLER CONDITIONS LASTING WELL
INTO THE COMING WEEK.

&&

.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 323 PM EDT WED MAY 27 2015

THREAT FOR SEVERE THUNDERSTORMS HAS SHIFTED EAST OUT OF SOUTH
CENTRAL LOWER MICHIGAN. BEHIND THIS...PATCHES OF LIGHT RAIN WERE
MOVING EAST INTO THE AREA FROM LAKE MICHIGAN. FAR GREATER COVERAGE
OF RAIN IS NOTED OVER NORTHERN LOWER MICHIGAN...SO HAVE KEPT BEST
POPS OVER OUR NORTHERN ZONES INTO TONIGHT. EXPECT PATCHY FOG TO
DEVELOP AREAWIDE MAINLY AFTER MIDNIGHT.

AFTER A DRY THURSDAY...ATTENTION TURNS TO SHOWERS AND THUNDERSTORMS
FRIDAY INTO SATURDAY. THE PATTERN WILL BE CHARACTERIZED BY A FAIRLY
PROGRESSIVE UPPER TROUGH WITH CONFLUENT FLOW DOWNSTREAM. THIS IS NOT
A SYNOPTIC PATTERN CONDUCIVE TO SIGNIFICANT HEAVY RAIN. ALTHOUGH
DEEP LAYER FLOW PARALLELS THE ASSOCIATED COLD FRONT...THE SYSTEM
OVERALL SEEMS PROGRESSIVE ENOUGH TO MITIGATE THE FLOODING THREAT.
NONETHELESS...THIS WILL BE SOMETHING TO MONITOR. PLEASE REFERENCE
THE HYDROLOGY SECTION FOR FURTHER DETAILS.

.LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY)
ISSUED AT 323 PM EDT WED MAY 27 2015

FAIRLY QUIET WEATHER IN THE EXTENDED. THE COLD FRONT PUSHES THROUGH
ON SATURDAY EVENING WITH SHOWERS ENDING FROM NORTH TO SOUTH. IT
SHOULD CLEAR OUT ACROSS THE NORTH BY MIDNIGHT AND TEMPERATURES ARE
EXPECTED TO DROP INTO THE 30S BY DAYBREAK SUNDAY...WITH FROST
FORMATION POSSIBLE ACROSS THE NORTHERN THIRD OF THE FORECAST AREA.
FROST IS ALSO POSSIBLE ACROSS THE NORTHERN ZONES ON MONDAY MORNING
AS COOL SFC HIGH HOLDS SWAY.

THE HIGH MOVES EAST ON TUESDAY WITH A RETURN FLOW SETTING UP ON
WEDNESDAY. SOME SHOWERS AND POSSIBLY THUNDER CAN BE EXPECTED ACROSS
THE SOUTHERN ZONES BY WEDNESDAY AFTERNOON IN AREA OF WEAK ISENTROPIC
ASCENT.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 702 AM EDT WED MAY 27 2015

IFR AND LOWER CLOUDS WILL MOVE IN OFF OF LAKE MI IMPACTING MAINLY
KMKG THIS MORNING. CONDITIONS SHOULD IMPROVE IN THE AFTERNOON.
THUNDERSTORMS WILL LIKELY DEVELOP EARLY THIS AFTERNOON CLOSE TO
KBTL AND KLAN...BUT TRACK QUICKLY EAST. THE MAIN IMPACT SITE
SHOULD BE KJXN. EVEN WITHOUT STORMS...THE WIND WILL BE GUSTY
THROUGHOUT SW LOWER WITH SOME VALUES OVER 30 KNOTS LIKELY TODAY.

MVFR FOG COULD DEVELOP LATER TONIGHT. CONFIDENCE IS NOT THAT HIGH
ON THIS HAPPENING.

&&

.MARINE...
ISSUED AT 323 PM EDT WED MAY 27 2015

CANCELED THE MARINE FOG ADVISORY BASED ON WEBCAMS...ALTHOUGH PATCHY
FOG IS EXPECTED OVERNIGHT. WINDS AND WAVES ARE EXPECTED TO REMAIN
WELL BELOW ADVISORY THRESHOLDS THROUGH THURSDAY NIGHT...ALTHOUGH
WINDS WILL BEGIN TO PICK UP ON FRIDAY.

&&

.HYDROLOGY...
ISSUED AT 1246 PM EDT WED MAY 27 2015

RIVER LEVELS ARE LOW AND STABLE ACROSS THE AREA. HAD 1/2 TO 3/4
OF AN INCH OF PRECIPITATION WITH THIS MOST RECENT SYSTEM... AND
SOME SMALL UP TICS NOTED ON AREA RIVERS. EXPECTING NO FLOODING
THROUGH THE WEEK.

A POTENTIAL FOR MORE RAIN FRIDAY INTO SATURDAY (OVER AN INCH) MAY
PUSH SOME STREAMS AND RIVERS ABOVE BANKFULL BY NEXT WEEK... IF
THESE AMOUNTS ARE REALIZED.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&

$$

SYNOPSIS...TJT
SHORT TERM...TJT
LONG TERM...OSTUNO
AVIATION...MJS
HYDROLOGY...63
MARINE...TJT


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