461  
FXUS63 KGRR 200830  
AFDGRR  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE GRAND RAPIDS MI  
330 AM EST SUN JAN 20 2019  
 
LATEST UPDATE...  
SYNOPSIS/DISCUSSION/MARINE  
   
SYNOPSIS
 
 
ISSUED AT 330 AM EST SUN JAN 20 2019  
 
- LAKE EFFECT SNOW TO CLIP THE POINTS TODAY  
 
- COLD WIND CHILL VALUES THIS MORNING AND POSSIBLY AGAIN TONIGHT  
 
- SNOW/WINTRY MIX WITH SYSTEM ON TUESDAY INTO WEDNESDAY  
 

 
   
DISCUSSION
 
(TODAY THROUGH NEXT SATURDAY)  
ISSUED AT 330 AM EST SUN JAN 20 2019  
 
FIRST ORDER OF BUSINESS IS TO ADDRESS THE THREAT OF LAKE EFFECT SNOW  
FROM EARLY THIS MORNING THROUGH THE DAY UP NEAR BIG AND LITTLE SABLE  
POINTS. HIGH RESOLUTION MODELS LIKE THE 4KM NAM AND THE NMM ARE  
INDICATING NORTH FLOW LAKE EFFECT SNOW BANDS MOVING INTO BOTH BIG  
AND LITTLE SABLE POINTS. FOR NOW WE ARE MOST COMFORTABLE IN THE BAND  
AFFECTING BIG SABLE POINT AND MASON COUNTY, BUT IT NOT OUT OF THE  
REALM OF POSSIBILITIES THAT WE MAY NEED TO EXTEND THE ADVISORY INTO  
OCEANA COUNTY AS WELL. SNOWFALL ACCUMULATIONS COULD REACH THE 2 TO 5  
INCH RANGE BY THIS EVENING WITH THE HIGHEST TOTALS FROM LUDINGTON  
NORTH UP THE SHORE TO BIG SABLE POINT AT THE STATE PARK.  
 
WE WILL MAINTAIN THE WIND CHILL ADVISORY AS IS, WE ARE CURRENTLY  
GETTING WIND CHILLS IN THE ADVISORY RANGE AT MANY SITES IN THE -15  
TO -20F RANGE. AS WE "WARM" SLIGHTLY THIS MORNING WE WILL RISE ABOUT  
THE -15F THRESHOLD. ANOTHER ITEM TO MONITOR IS THE POTENTIAL NEED  
FOR ANOTHER WINCH CHILL ADVISORY TONIGHT IN THE NORTHEAST AND  
SOUTHEAST CORNERS OF THE FORECAST AREA. OVERNIGHT WE ONCE AGAIN DIP  
TO COLDER THAN -15F IN THESE AREAS. WE DECIDED NOT TO CONFUSE THE  
HEADLINES AND LET OUT EXISTING ONE PLAY OUT FIRST.  
 
A SYSTEM TUESDAY INTO WEDNESDAY WILL BRING ANOTHER ROUND OF WINTER  
WEATHER TO THE FORECAST AREA. A MODERATING IN 850MB TEMPERATURES  
WILL BRING A WINTRY MIX BACK INTO THE FORECAST AREA. IT APPEARS WE  
WILL SEE SOME ACCUMULATING SNOW IN MANY AREAS WITH THE HIGHEST  
TOTALS ACROSS CENTRAL LOWER MICHIGAN, IN POSSIBLY THE 3-5 INCH  
RANGE. LESSER AMOUNTS ARE EXPECTED TO THE SOUTH ALONG I-94. THE BEST  
CHANCE FOR A MIX WILL OCCUR ALONG AND SOUTH OF I-96 IT APPEARS. WE  
HAVE SOME TIME TO NAIL THIS DOWN HOWEVER.  
 
A SURGE OF COLDER AIR IS STILL POISED TO AFFECT LOWER MICHIGAN NEXT  
WEEKEND.  
 

 
   
AVIATION
 
(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)  
ISSUED AT 1251 AM EST SUN JAN 20 2019  
 
ALL BUT JXN ARE VFR AND WILL REMAIN THAT WAY THROUGH THE PERIOD.  
JXN WILL CLIMB TO VFR LATER THIS MORNING.  
 

 
   
MARINE
 
 
ISSUED AT 330 AM EST SUN JAN 20 2019  
 
WE HAVE EXPANDED THE HEAVY FREEZING SPRAY WARNING AND SMALL CRAFT  
ADVISORY TO ALL MARINE ZONES. IN ADDITION, WE EXTENDED IT IN TIME  
THROUGH TONIGHT. LOOKING AT HIGH RESOLUTION MODELS LIKE THE 4KM NAM,  
THERE ARE TIMES WHERE THE NORTHERLY WINDS JUMP INTO THE 20-30 KNOT  
RANGE BOTH TODAY AND TONIGHT IN ALL ZONES. THE BUFKIT OVERVIEW AT  
THE MID LAKE POINT IS MOST TELLING AND IS LIKELY INDICATIVE OF MOST  
OF OUR NEARSHORE WATERS ESPECIALLY GIVEN THE NORTH FLOW. WITH  
TEMPERATURES IN THE TEENS AND SINGLE DIGITS AND WINDS IN EXCESS OF  
22 KNOTS, HEAVY FREEZING SPRAY IS LIKELY. WAVES WILL REACH THE 3 TO  
6 FOOT RANGE IN MOST ZONES.  
 

 
   
HYDROLOGY
 
 
ISSUED AT 325 PM EST SAT JAN 19 2019  
 
VERY COLD TEMPERATURES TONIGHT THROUGH TUESDAY MORNING WILL CAUSE  
SIGNIFICANT ICE GROWTH IN RIVERS. THIS MAY CAUSE ICE JAMS TO FORM,  
AND COULD LEAD TO RAPID CHANGES IN WATER LEVELS AND LOCALIZED  
FLOODING IN PRONE AREAS.  
 
THE NEXT WIDESPREAD PRECIPITATION EVENT IS EXPECTED TUESDAY NIGHT  
THROUGH WEDNESDAY MORNING, AND WILL BE A COMBINATION OF SNOW AND  
RAIN (ALL SNOW ALONG AND NORTH OF M-10). RAIN AND WATER EQUIVALENT  
FROM SNOW MAY REACH NEAR ONE-QUARTER OF AN INCH.  
 
PRECIPITATION FOR THE REMAINDER OF THE WEEK WILL OCCUR AS SEVERAL  
LIGHT SNOW EVENTS. TEMPERATURES WILL BRIEFLY WARM INTO THE 20S AND  
30S FOR HIGHS MIDWEEK, BEFORE WE RETURN INTO A VERY COLD PATTERN  
THAT WILL FAVOR ICE GROWTH/REGROWTH FOR THE END OF THE WEEK.  
 

 
   
GRR WATCHES/WARNINGS/ADVISORIES
 
 
MI...WIND CHILL ADVISORY UNTIL 10 AM EST THIS MORNING FOR MIZ038>040-  
044>046-051-052-056>059-064>067-072>074.  
 
WINTER WEATHER ADVISORY UNTIL 7 PM EST THIS EVENING FOR MIZ037.  
 
LM...HEAVY FREEZING SPRAY WARNING UNTIL 6 AM EST MONDAY FOR  
LMZ844>849.  
 
SMALL CRAFT ADVISORY UNTIL 6 AM EST MONDAY FOR LMZ844>849.  
 

 
 

 
 
SYNOPSIS...DUKE  
DISCUSSION...DUKE  
AVIATION...04  
HYDROLOGY...OSTUNO  
MARINE...DUKE  
 
CLICK HERE TO GO TO PREVIOUS BULLETINS.

The Nexlab MI Page
The Nexlab IN Page Main Text Page