000
FXUS63 KGRR 170023
AFDGRR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
823 PM EDT SUN JUN 16 2013

LATEST UPDATE...
UPDATE

.SYNOPSIS...
ISSUED AT 340 PM EDT SUN JUN 16 2013

MAINLY DRY WEATHER IS EXPECTED TONIGHT AS SOUTHWEST LOWER MICHIGAN
IS SITUATED BETWEEN LOW PRESSURE SYSTEMS. A LOW PRESSURE SYSTEM
WILL TRAVERSE THE AREA ON MONDAY AND MONDAY EVENING BRINGING THE
AREA SOME SCATTERED SHOWERS AND THUNDERSTORMS. DRY WEATHER WILL
RETURN FOR TUESDAY THROUGH THURSDAY. HIGHS WILL PUSH TO AROUND 80 ON
MONDAY...BUT DIP BACK INTO THE 70S BEHIND THE FRONT FOR THE MIDDLE
OF THE WEEK.

&&

.UPDATE...
ISSUED AT 817 PM EDT SUN JUN 16 2013

WE HAVE UPDATED THE FCST THIS EVENING TO ADD IN THE CHANCE OF A
FEW STORMS ACROSS THE NW COUNTIES. A COUPLE OF STORMS THAT FORMED
ACROSS NE WISCONSIN EARLIER ARE SURVIVING THE TRIP ACROSS THE LAKE
EARLY THIS EVENING. THIS INDICATES THAT SHORT WAVE MOVING INTO NRN
MI IS OVERCOMING A MORE STABLE LOW LEVEL ENVIRONMENT OVER THE
LAKE. THERE IS OVER 500 J/KG OF CAPE OVER MOST OF THE AREA WITH
SOME LOCATIONS EVEN UP AROUND 1000 J/KG PER THE SPC MESO PAGE. WE
EXPECT THEY SHOULD DIE OFF A BIT WITH PEAK HEATING HAVING
PASSED...BUT THE SHORT WAVE MAY LET THEM SURVIVE A BIT LONGER.

&&

.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 340 PM EDT SUN JUN 16 2013

MAIN FORECAST ISSUE IN THE SHORT TERM PERTAINS TO PRECIPITATION
POTENTIAL FROM LATE TONIGHT THROUGH MONDAY EVENING. A WEAK LOW WILL
DROP INTO LOWER MICHIGAN FROM THE NORTHWEST LATE TONIGHT AND PUSH
THROUGH THE STATE MONDAY AND MONDAY EVENING. A SHORTWAVE TROUGH WILL
PIVOT THROUGH THE REGION AS WELL...RIGHT DURING MAX HEATING ON
MONDAY. MODELS INDICATE THAT MOISTURE POOLS ALONG THE SURFACE TROUGH
AND THERE WILL BE ENOUGH INSTABILITY AND LIFT TO KICK OFF SCATTERED
CONVECTION. THERE LOOKS TO BE A LAKE SHADOW...SO THE BEST CHANCES
FOR PRECIPITATION WILL BE INLAND TOWARD MOP/LAN AND JXN. THE
PRECIPITATION WILL BE CENTERED IN THE AFTERNOON AND EVENING...BUT
CANNOT RULE OUT SOME LIGHT RAIN SHOWERS OR AN ISOLATED THUNDERSTORM
MOVING IN FROM THE NORTH LATE TONIGHT AND MONDAY MORNING.

A WEAK LLJ IS NOTED ALONG WITH WEAK 850MB MOISTURE TRANSPORT. A
STRONGER MID LEVEL SPEED MAX IS PRESENT AT 50+ KNOTS. SO...IF
MOISTURE CREEPS UP ENOUGH IN THE LOW LEVELS TO 60F DEW POINTS THERE
MAY BE A FEW STRONG STORMS AT MAX HEATING THAT MAY CONTAIN
MARGINALLY SEVERE HAIL AND WIND.

DRIER AIR PUSHES IN BEHIND THE FRONT MONDAY NIGHT WITH DRY
CONDITIONS EXPECTED FROM OVERNIGHT MONDAY NIGHT THROUGH TUESDAY
NIGHT.

.LONG TERM...(WEDNESDAY THROUGH SUNDAY)
ISSUED AT 340 PM EDT SUN JUN 16 2013

COOL AND DRY WEATHER WILL START THE LONG TERM PERIOD WITH HIGH
PRESSURE EXPECTED TO BE OVER LOWER MI.  HOWEVER EACH DAY...FROM
THURSDAY THROUGH SUNDAY...SHOULD SEE TEMPS WARM.  LOW TO MID 80S
SHOULD BE COMMON BY NEXT WEEKEND.

DRY WEATHER IS EXPECTED THROUGH FRIDAY OR FRIDAY NIGHT WHEN AN UPPER
RIDGE OVER THE MIDDLE OF THE NATION BEGINS TO BREAK DOWN.  THIS
SHOULD ALLOW SMALL BUT POTENTIALLY POTENT SHORT WAVES TO CROSS ALONG
THE NORTHERN STREAM.  GULF MOISTURE SHOULD PUSH DEW POINTS INTO THE
MID AND UPPER 60S.  EXPECT HUMID CONDITIONS ALONG WITH SCATTERED
STORMS INTO THE WEEKEND.

&&

.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 743 PM EDT SUN JUN 16 2013

VFR CONDITIONS SHOULD PREVAIL AT MOST TERMINALS OVERNIGHT.
HOWEVER...PATCHY FOG WILL BE POSSIBLE AFTER 06Z ESPECIALLY WHEREVER
WINDS MANAGE TO GO CALM. THIS IS A LOW CONFIDENCE SCENARIO AT MOST
TERMINALS AND IS THEREFORE NOT MENTIONED IN THE TAFS. JXN WOULD BE
THE MOST LIKELY EXCEPTION...SO DID MENTION FOG THERE.

ADDED CB TO MOST TAF SITES AFTER 16Z MONDAY. BEST CHANCES FOR
THUNDERSTORMS WOULD BE AT THE EASTERNMOST SITES...JXN...LAN...AND
BTL.


&&

.MARINE...
ISSUED AT 340 PM EDT SUN JUN 16 2013

STUBBORN MARINE FOG CONTINUES FROM ABOUT PORT SHELDON NORTH UP THE
COAST TOWARD LITTLE SABLE POINT. STILL EXPECTING IT TO MIX OUT...BUT
WILL CARRY AREAS OF FOG WORDING THROUGH THE EVENING. WINDS AND WAVES
ARE EXPECTED TO REMAIN BELOW ADVISORY CRITERIA...DESPITE AN INCREASE
IN WESTERLY FLOW TONIGHT AND NORTHERLY FLOW TOMORROW NIGHT. FEEL THE
BETTER WINDS WILL NOT MIX DOWN TONIGHT AND THE FLOW GOES OFF SHORE
MONDAY NIGHT.


&&

.HYDROLOGY...
ISSUED AT 340 PM EDT SUN JUN 16 2013

5 RIVER ADVISORIES CONTINUE TODAY. EAGLE WAS ADDED BACK INTO THE
LIST OF ADVISORIES AS LAST NIGHT/S RAINS PUSHED IT ABOVE BANK FULL
ONCE AGAIN. SEVERAL SWATHS OF ABOVE ONE INCH RAINS OCCURRED LAST
NIGHT WHERE THUNDERSTORMS TRAINED. THE HEAVIEST TOTAL RECEIVED TODAY
WAS 2.40 INCHES UP NEAR MONTAGUE. PRECIPITATION EXPECTED WITH THE
NEXT SYSTEM (MON/MON EVE) SHOULD NOT BE OVERLY HEAVY...GENERALLY
LESS THAN A HALF INCH...SO RIVER LEVELS ARE NOT EXPECTED TO BE
AFFECTED MUCH. DRY WEATHER IS THEN FORECAST THROUGH MID WEEK...SO
RIVERS SHOULD GRADUALLY BEGIN TO FALL AS WE PROGRESS THROUGH THE
WEEK.

&&

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

$$

UPDATE...NJJ
SYNOPSIS...DUKE
SHORT TERM...DUKE
LONG TERM...JK
AVIATION...TJT
HYDROLOGY...DUKE
MARINE...DUKE