Area Forecast Discussion
Issued by NWS Grand Rapids, 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 KGRR 020729
AFDGRR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
329 AM EDT TUE JUN 2 2015

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

.SYNOPSIS...
ISSUED AT 329 AM EDT TUE JUN 2 2015

HIGH PRESSURE WILL GIVE US TWO DAYS OF SUNNY SKIES AND LIGHT
WINDS. AFTERNOON TEMPERATURE ARE EXPECTED TO WARM EACH DAY.
MEANWHILE A CANADIAN COLD FRONT PUSHES THROUGH THE AREA ON
THURSDAY AFTERNOON WITH SCATTERED SHOWERS OVER NORTHERN SECTIONS.
THE FRONT THEN STALLS JUST SOUTH OF THE AREA BY FRIDAY MORNING.
THEN THE FRONT WILL PUSH BACK AS A WARM FRONT LATER FRIDAY. THAT
WILL BRING THE THREAT OF SHOWERS AND A FEW THUNDERSTORMS TO THE
AREA THEN. THERE IS THE TREAT OF A MORE SIGNIFICANT STORM SYSTEM
TO MOVE THROUGH THE AREA FOR SUNDAY.

&&

.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 329 AM EDT TUE JUN 2 2015

LITTLE GOING ON THE SHORT TERM TO BE CONCERNED WITH. THE PASSAGE
OF A WEAK COLD FRONT THURSDAY AFTERNOON COULD TRIGGER A FEW
SHOWERS NEAR AND NORTH OF ROUTE 10.

OUT BIG PICTURE VIEW OF THE WEATHER IS WE HAVE SPLIT FOR WITH THE
SOUTHERN STREAM COMING ACROSS THE NORTH PACIFIC OCEAN INTO WESTERN
NORTH AMERICAN. THE NORTHERN STREAM IS MOSTLY NORTH OF 55N WHILE
THE SOUTHERN STREAM IS AROUND 35N OVER THE PACIFIC BUT NEAR TO 45N
OVER MICHIGAN. THAT CREATES UPPER CONVERGENCE WHICH IS GREAT FOR
MOSTLY CLEAR SKIES. HOWEVER THIS IS NOT TO LAST. A VERY LARGE
STORM IS FORECAST BY ALL MODELS TO FORM IN THE GULF OF ALASKAN BY
THURSDAY AND THAT CONSOLIDATES BOTH JET STREAMS. THE RESULTS IN A
ROSSY WAVE PROPAGATION WHICH IN TURN WILL RESULT IN A DEEP TROUGH
OVER EASTERN NORTH AMERICA BY THE MIDDLE OF NEXT WEEK. THE
TRANSITION TO THAT PATTERN WILL BRING WARMER TEMPERATURES AND
CONVECTION LATE THIS WEEK INTO EARLY NEXT WEEK. THAN AS THE UPPER
TROUGH DEEPS COOLER AND DRY WEATHER WILL FOLLOW.

THE FRONT ON THURSDAY IS JUST THE FIRST SIGN OF THIS CHANGE. THE
FRONT WILL BE MOISTURE STAVED AND THERE IS LITTLE IN THE WAY OF
INSTABILITY SO I EXPECT ONLY A FEW SHOWERS OVER OUR NORTHERN CWA
IN THE AFTERNOON.

.LONG TERM...(THURSDAY NIGHT THROUGH MONDAY)
ISSUED AT 329 AM EDT TUE JUN 2 2015

A COLD FRONT WILL BRING A CHANCE OF SHOWERS AND THUNDERSTORMS LATE
THURSDAY NIGHT AND FRIDAY. A CONSENSUS OF MEDIUM RANGE GUIDANCE
SUGGESTS ONLY WEAK INSTABILITY WILL DEVELOP FRIDAY. 00Z ECMWF
GUIDANCE HAS THE RELATIVELY BETTER CHANCE FOR CONVECTION AS IT
SUGGESTS THAT SB CAPE VALUES COULD POTENTIALLY REACH 1000-1500 J/KG
FRIDAY AFTERNOON NEAR TO MAINLY EAST OF US-131.

A CONSENSUS OF LATEST MEDIUM RANGE GUIDANCE STILL SUGGESTS THAT HIGH
PRESSURE SHOULD BUILD IN BEHIND THAT SYSTEM TO PRODUCE FAIR WX FOR
SATURDAY.

A NORTHERN STREAM LOW PRESSURE SYSTEM WILL BRING ANOTHER CHANCE OF
SHOWERS AND THUNDERSTORMS ON SUNDAY INTO MONDAY. FAIR WEATHER SHOULD
RETURN BEHIND THAT SYSTEM FOR THE MIDDLE PORTION OF NEXT WEEK.
TEMPERATURES SHOULD AVERAGE RATHER CLOSE TO NORMAL THROUGH THE LONG
RANGE FORECAST PERIOD.


&&

.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY)
ISSUED AT 1210 AM EDT TUE JUN 2 2015

VFR CONDITIONS WILL CONTINUE THROUGH TUESDAY AND TUESDAY NIGHT. SFC
WINDS WILL BE OUT OF THE EAST/NORTHEAST AT LESS THAN 10 KTS. A LAKE
BREEZE WILL CAUSE WINDS TO SHIFT TO THE WEST EARLY TUESDAY AFTERNOON
AT KMKG.


&&

.MARINE...
ISSUED AT 329 AM EDT TUE JUN 2 2015

HIGH PRESSURE MEANS LIGHT WINDS AND DRY AIR SO GREAT WEATHER LOW
WAVES AND LIGHT WINDS IN OUR NEAR SHORE AREA.

&&

.HYDROLOGY...
ISSUED AT 1033 AM EDT MON JUN 1 2015

MOST OF THE SMALLER RIVERS AND HEADWATERS THAT HAVE EXPERIENCED RISES
AFTER THE RECENT RAINFALL HAVE BEGUN TO STABILIZE OR FALL. A
NUMBER OF DOWNSTREAM RIVERS ARE STILL RISING SLOWLY. NO FLOODING
IS EXPECTED. DRY WEATHER IS EXPECTED OVER AT LEAST THE NEXT FEW
DAYS.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...FROST ADVISORY UNTIL 8 AM EDT THIS MORNING FOR MIZ037>040-
     043>046-051.

LM...NONE.
&&

$$

SYNOPSIS...WDM
SHORT TERM...WDM
LONG TERM...LAURENS
AVIATION...LAURENS
HYDROLOGY...CAS
MARINE...WDM



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