Area Forecast Discussion
Issued by NWS Grand Rapids, MI

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000
FXUS63 KGRR 261617
AFDGRR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
1220 PM EDT SAT JUL 26 2014

LATEST UPDATE...
AVIATION

.SYNOPSIS...
ISSUED AT 324 AM EDT SAT JUL 26 2014

THERE`S A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS TODAY, BUT A
BETTER CHANCE SUNDAY. WE/LL SEE A LITTLE SUNSHINE TODAY ALONG WITH
SOME CLOUDS. IT WILL BE NOTICEABLY MORE HUMID TODAY AS SOUTH WINDS
PUSH MORE MOISTURE NORTHWARD. AFTER SUNDAY`S STORMS...SOME OF WHICH
MAY BE STRONG...COOLER WEATHER WILL DEVELOP MONDAY. TEMPERATURES
WILL STRUGGLE TO REACH 70 MONDAY...SO DEFINITELY CHILLY FOR THE END
OF JULY. THE COOLER WEATHER WILL ONLY LAST A COUPLE OF DAYS BEFORE A
WARMING DEVELOPS.

&&

.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 324 AM EDT SAT JUL 26 2014

FORECAST CONCERNS DEAL WITH CONVECTIVE TRENDS THROUGH THE PERIOD.

OVERALL...AM NOT IMPRESSED WITH PCPN POTENTIAL TODAY. IT/S NOT
ZERO...BUT IT`S NOT REAL HIGH EITHER. A THUNDERSTORM HAS RECENTLY
DEVELOPED OVER NORTH CENTRAL WISCONSIN AND IS MOVING ESE. THIS IS
ASSOCIATED WITH A WEAK SHORT WAVE THAT WILL MOVE OVER NORTHERN
LOWER. WE`VE GONE WITH CHC POPS OVER THE NRN CWA AND SLIGHT CHC
ACROSS THE SOUTH. THEN DRY TONIGHT.

WV IMAGERY SHOWS A WRAPPED UP SHORT WAVE OVER WESTERN MANITOBA. THIS
LOW WILL DROP SOUTHEAST AND ACROSS THE CWA SUNDAY IN CONJUNCTION
WITH A SFC LOW. THIS SYSTEM HAS SOME STRONG DYNAMICS WITH IT. LI/S
NEAR -6C/SBCAPE NEAR 2500 J/KG /0-6KM BULK SHEAR 40-50KTS.
ORDINARILY...THIS WOULD BE A RECIPE FOR SEVERE STORMS. HOWEVER...THE
TRACK OF THE LOW DIRECTLY ACROSS THE CENTRAL CWA SUGGESTS THAT THE
STRONGEST STORMS MAY REMAIN JUST SOUTH OF THE CWA IN NORTHERN
INDIANA SUNDAY. THIS IS WHERE SLIGHT AND MODERATE RISKS ARE. THAT
SAID...A FEW STRONGER STORMS CERTAINLY WILL BE POSSIBLE ALONG/SOUTH
OF I-94.

AS THE LOW MOVES BY LATE SUNDAY...A SECONDARY COLD FRONT WILL DROP
SOUTH AND GENERATE A FEW SHOWERS. THESE SHOWERS WILL LINGER INTO
MONDAY AS COLDER AIR ALOFT MOVES OVER LOWER MICHIGAN AND STEEPER
LAPSE RATES DEVELOP. MONDAY WILL BE MUCH COOLER WITH HIGHS IN THE
UPPER 60S/LOWER 70S.

.LONG TERM...(MONDAY NIGHT THROUGH FRIDAY)
ISSUED AT 324 AM EDT SAT JUL 26 2014

LONG TERM PERIOD IS DOMINATED BY UPPER TROUGHING THAT IS IN PLACE
ALMOST THE ENTIRE TIME FRAME. THE TROUGH IS AT ITS DEEPEST IN THE
FIRST COUPLE FORECAST PERIODS...MONDAY NIGHT AND TUESDAY WITH
HEIGHTS RISING A BIT EACH DAY THROUGH THE REMAINDER OF THE WEEK.

WE ARE LOOKING AT DIURNALLY DRIVEN SHOWERS AND POSSIBLY A FEW
THUNDERSTORMS IN AND AROUND PEAK HEATING IN THE AFTERNOON AND EARLY
EVENING. THERE IS NOT MUCH IN THE WAY OF SURFACE FEATURES TO KEY
ON...SO WITH THE UPPER JET SOUTH OF THE GREAT LAKES THE COOL MID
LEVEL/JULY HEATING REGIME SHOULD RESULT IN DAILY SHOWERS/STORMS.

IN REGARD TO TEMPERATURES...THE START OF THE WEEK WILL BE
COOL...WITH GRADUALLY WARMING TEMPERATURES. NORMAL HIGHS ARE IN THE
LOWER 80S THIS TIME OF YEAR. HIGHS SHOULD WARM EACH DAY FROM THE LOW
70S ON TUESDAY TO AROUND 80 BY WEEKS END.

&&

.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY)
ISSUED AT 1220 PM EDT SAT JUL 26 2014

VFR CONDITIONS WILL CONTINUE AT ALL THE TERMINALS THIS AFTERNOON AND
EVENING WITH MAINLY DRY CONDITIONS. AN ISOLATED SHOWER MAY POP UP
THIS AFTERNOON BUT THERE IS NOT ENOUGH POTENTIAL TO WARRANT MENTION
OF IT IN ANY OF THE TERMINAL FORECASTS.

CONDITIONS WILL GRADUALLY DETERIORATE FROM VFR TO MVFR DURING THE
EARLY MORNING HOURS SUNDAY DUE TO SOME PATCHY FOG AND LOW CLOUDS.
WIDESPREAD DENSER FOG IS NOT ANTICIPATED.

SHOWERS AND THUNDERSTORMS WILL DEVELOP DURING THE LATE MORNING AND
EARLY AFTERNOON HOURS SUNDAY WITH MAINLY MVFR CONDITIONS
ANTICIPATED. HOWEVER BRIEF IFR/LIFR CONDITIONS POSSIBLE IN ANY
HEAVIER SHOWERS AND TSTORMS.

&&

.MARINE...
ISSUED AT 324 AM EDT SAT JUL 26 2014

SOUTHWEST WINDS 5 TO 15 KNOTS WILL RESULT IN 1 TO 2 FOOT WAVES
TODAY. STRONGER WINDS AND CONSEQUENTLY HIGHER WAVES ARE EXPECTED
SUNDAY NIGHT INTO MONDAY AS A PUSH OF COLDER AIR FLOWS DOWN THE
LAKE. A SCA WILL PROBABLY BE NEEDED DURING THAT TIME FRAME.


&&

.HYDROLOGY...
ISSUED AT 1207 PM EDT SAT JUL 26 2014

THE MAIN PRECIPITATION THREAT WILL BE SUNDAY AS MOISTURE EDGES UP
INTO THE AREA. PWAT VALUES PUSH BETWEEN 1.0 TO 1.5 INCHES DURING
THE AFTERNOON. THIS MAY RESULT IN LOCALIZED HEAVY RAINFALL IN AND
AROUND THUNDERSTORMS. HOWEVER...AREA AVERAGES ARE MORE LIKELY TO
RANGE FROM ONE-QUARTER TO ONE-HALF AN INCH. PRECIPITATION THEN
SEEMS TO LINGER INTO MONDAY BUT SHOULD NOT BE OF ANY GREAT
SIGNIFICANCE IN THE MONDAY MORNING TIME FRAME.

ASIDE FROM SUNDAYS FOCUS...WE WILL SEE MAINLY DRY CONDITIONS TODAY.
ADDITIONAL CHANCES FOR LIGHT RAIN EXIST AS WE HEAD THROUGH THE NEW
WORK WEEK. NO HIGH END PRECIPITATION EVENTS ARE ANTICIPATED TO AFFECT
THE AREA. RIVERS CONTINUE TO RUN WELL BELOW ACTION STAGE...SO NO
CONCERN FOR RIVER FLOODING AT THIS TIME.



&&

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

$$

SYNOPSIS...93
SHORT TERM...93
LONG TERM...DUKE
AVIATION...LAURENS
HYDROLOGY...JAM
MARINE...93








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