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000
FXUS63 KGRR 281144
AFDGRR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
744 AM EDT MON JUL 28 2014

LATEST UPDATE...
AVIATION

.SYNOPSIS...
ISSUED AT 327 AM EDT MON JUL 28 2014

COOLER AND DRIER AIR IS FLOWING SOUTH FROM CANADA. HIGH TEMPERATURES
WILL STRUGGLE TO REACH 70 TODAY. GENERALLY DRY WEATHER IS EXPECTED
TODAY. BY TUESDAY...SHOWERS AND THUNDERSTORMS ARE POSSIBLE
ESPECIALLY DURING THE AFTERNOON. A FEW OF THE STORMS COULD PRODUCE
SOME SOME SMALL HAIL. A SLOW WARMING TREND WILL TAKE HIGHS TO THE
UPPER 70S BY THE END OF THE WEEK...WHICH IS STILL WELL BELOW NORMAL.

&&

.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 327 AM EDT MON JUL 28 2014

FORECAST CONCERNS DEAL WITH THE CONVECTIVE POTENTIAL TUESDAY. SFC
HIGH PRESSURE WILL MOVE OVER THE GREAT LAKES TUESDAY. THAT WILL
LIKELY GIVE US SOME SUNSHINE. AT THE SAME TIME MUCH COOLER AIR
ALOFT...H5 TEMPS FALLING TO -17C WILL CREATE STEEP LAPSE RATES. LI`S
NEAR -1C AND MUCAPE AROUND 700 J/KG COUPLED WITH THE COMBINATION OF
THE HEATING AND INSTABILITY ALOFT WILL PROBABLY RESULT IN
THUNDERSTORM DEVELOPMENT...ESPECIALLY DURING THE AFTERNOON. AND SOME
OF THE STORMS THAT DEVELOP WILL PROBABLY PRODUCE SOME SMALL HAIL.

COOL TEMPS ALOFT ON WEDNESDAY MAY RESULT IN SOME SHRA/TSRA
DEVELOPMENT TOO. HOWEVER THE DYNAMICS WEDNESDAY ARE NOT AS STRONG AS
TUESDAY SO OUR POPS ARE LOWER.

FOR TODAY WE/LL SEE SOME SUNSHINE. RADAR TRENDS CONTINUE TO SHOW A
DECREASE IN SHOWER ACTIVITY AND DRY WX IS EXPECTED BY 12Z. LATEST IR
LOOP SHOWS CLOUDS DISSIPATING FROM NORTH TO SOUTH AND SO WE EXPECT
SOME SUNSHINE TODAY. VERY COOL WEATHER FOR LATE JULY THOUGH WITH
HIGHS AROUND 70.

.LONG TERM...(WEDNESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 327 AM EDT MON JUL 28 2014

NO SIGNIFICANT CHANGES WERE MADE TO THE FORECAST THIS MORNING AS IT
STILL LOOKS ON TRACK. 00Z MODEL RUNS CONTINUE THE THEME OF UPPER
TROUGHING THROUGH THE LONG TERM. TOWARDS THE END OF THE WEEK AND
INTO NEXT WEEKEND THE UPPER TROUGH IS BEGINNING TO LIFT OUT TO THE
NORTHEAST ACROSS CANADA...BUT THERE IS STILL SOME TROUGHING THAT
PERSISTS. AT THE SURFACE FEATURES REMAIN RELATIVELY WEAK...THERE
ISN/T MUCH TO KEY ON. EXPECT SOME WEAK TROUGHS TO MOVE THROUGH
ASSOCIATED WITH MID LEVEL SHORTWAVES PIVOTING AROUND THE UPPER LOW.

EXPECT SOME DIURNAL SHOWERS AND A FEW STORMS EACH AFTERNOON AND
EVENING AROUND THE TIME OF MAX HEATING. HAVE POPS NEAR 30 PCT EACH
DAY DURING THE THURS-SAT TIME FRAME. HAVE SUNDAY DRY AT THIS POINT
BUT IT MAY BE ANOTHER DAY WITH SOME DIURNAL PRECIP AS WELL.

HIGH TEMPERATURES WILL BE NEAR TO SLIGHTLY BELOW NORMAL THROUGH THE
PERIOD. EXPECTING HIGHS IN THE UPPER 70S TO AROUND 80 EACH DAY.

&&

.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 744 AM EDT MON JUL 28 2014

SOME MVFR CLOUDS WILL LINGER ACROSS THE AREA THROUGH 15Z OR
SO...WITH VFR CONDITIONS EXPECTED THERE AFTER. CEILINGS IN THE
1000-3000FT RANGE THIS MORNING SHOULD LIFT INTO THE 3500-5000FT
RANGE FOR THIS AFTERNOON. TONIGHT...BROKEN CEILINGS AROUND 5000FT
ARE EXPECTED TO SWEEP THROUGH THE AREA FROM OF THE NORTH.
CONDITIONS WILL BE RELATIVELY DRY TODAY WITH A GUSTY NORTH-
NORTHWEST WIND OF 10-22 KNOTS. WINDS WILL TURN LIGHT TONIGHT.

&&

.MARINE...
ISSUED AT 327 AM EDT MON JUL 28 2014

NO CHANGES TO THE MARINE HEADLINES. SCA AND BEACH HAZARDS STATEMENT
REMAIN IN EFFECT. NORTH WINDS 15 TO 25 KNOTS WITH GUSTS TO 30 KNOTS
ARE EXPECTED. HIGHEST WAVES WILL BE IN THE SOUTHERN NEARSHORE ZONES
IN THE 5 TO 8 FOOT RANGE. HAZARDOUS SWIMMING CONDITIONS EXPECTED
TODAY.


&&

.HYDROLOGY...
ISSUED AT 314 PM EDT SUN JUL 27 2014

STORMS SHOULD KEEP MOVING ALONG THIS EVENING...SO WIDESPREAD HEAVY
BASIN RAINFALLS ARE NOT EXPECTED. LOCAL DOWNPOURS COULD LEAD TO
MORE THAN AN INCH OF RAIN IN AN HOURS TIME. THUS THE MAIN HYDRO
RISK FROM THIS SITUATION WILL BE URBAN AND POOR DRAINAGE FLOODING
THIS EVENING.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...BEACH HAZARDS STATEMENT THROUGH THIS EVENING FOR MIZ037-043-050-
     056-064-071.

LM...SMALL CRAFT ADVISORY UNTIL 6 AM EDT TUESDAY FOR LMZ844>849.

&&

$$

SYNOPSIS...93
SHORT TERM...93
LONG TERM...DUKE
AVIATION...DUKE
HYDROLOGY...MJS
MARINE...93