761  
FXUS21 KWNC 102029  
PMDTHR  
US HAZARDS OUTLOOK  
NWS CLIMATE PREDICTION CENTER COLLEGE PARK MD  
300 PM EST JANUARY 10 2018  
 
SYNOPSIS: AT THE START OF THE PERIOD, AN AREA OF DEEP SURFACE LOW PRESSURE IS  
FORECAST OVER THE NORTHERN MID-ATLANTIC. THE AREA OF SURFACE LOW PRESSURE IS  
ANTICIPATED TO MOVE INTO EASTERN CANADA JAN 14. AS THE AREA OF SURFACE LOW  
PRESSURE DEPARTS, CANADIAN SURFACE HIGH PRESSURE IS FORECAST TO MOVE FROM THE  
PLAINS ON JAN 13 TO THE CENTRAL AND EASTERN U.S. JAN 14-15. AN AREA OF  
REINFORCING SURFACE HIGH PRESSURE IS EXPECTED TO CROSS THE PLAINS TO THE  
CENTRAL U.S. JAN 15-16, AND THEN TO THE EAST-CENTRAL PART OF THE NATION JAN 17.  
AREAS OF SURFACE LOW PRESSURE ARE EXPECTED TO MOVE ACROSS THE ALEUTIANS TO THE  
GULF OF ALASKA JAN 13-17. DURING THE WEEK-2 PERIOD, THE OVERALL CIRCULATION  
PATTERN IS FORECAST TO BE PROGRESSIVE AND SOMEWHAT LESS AMPLIFIED AS  
UPPER-LEVEL LOW PRESSURE OVER THE EASTERN U.S. WEAKENS AND UPPER-LEVEL HIGH  
PRESSURE WEAKENS OVER THE INTERIOR WEST.  
 
HAZARDS  
 
PERIODS OF MUCH BELOW NORMAL TEMPERATURES FOR MUCH OF THE CENTRAL AND  
EAST-CENTRAL CONUS, SAT-WED, JAN 13-17.  
 
HEAVY PRECIPITATION FOR PARTS OF MAINE, SAT, JAN 13.  
 
HEAVY PRECIPITATION FOR PARTS OF THE SOUTH COAST OF MAINLAND ALASKA AND THE  
ALASKA PANHANDLE, SAT-SUN, JAN 13-14.  
 
MUCH ABOVE NORMAL TEMPERATURES FOR PARTS OF SOUTHERN ALASKA NEAR KODIAK ISLAND,  
ANCHORAGE, AND SOUTH OF THE ALASKA RANGE, SUN-MON, JAN 14-15.  
 
PERIODS OF HIGH WINDS FOR THE SOUTH COAST OF ALASKA, PARTS OF SOUTHWEST  
MAINLAND ALASKA, THE ALASKA PENINSULA, AND THE ALASKA PANHANDLE, SAT-MON, JAN  
13-15.  
 
PERIODS OF HIGH SIGNIFICANT WAVE HEIGHTS FOR THE SOUTH COAST OF ALASKA AND THE  
ALASKA PANHANDLE, SAT-TUE, JAN 13-16.  
 
SLIGHT RISK OF MUCH BELOW NORMAL TEMPERATURES FOR MUCH OF THE EASTERN THIRD OF  
THE CONUS, THU, JAN 18.  
 
MODERATE RISK OF MUCH BELOW NORMAL TEMPERATURES FOR PARTS OF THE EASTERN CONUS,  
THU, JAN 18.  
 
SLIGHT RISK OF HEAVY PRECIPITATION FOR MUCH OF THE WESTERN THIRD OF THE CONUS,  
THU-SAT, JAN 18-20.  
 
MODERATE RISK OF HEAVY PRECIPITATION FOR PARTS OF THE GREAT BASIN, THU-SAT, JAN  
18-20.  
 
HIGH RISK OF HEAVY PRECIPITATION FOR PARTS OF THE GREAT BASIN, THU-SAT, JAN  
18-20.  
 
SLIGHT RISK OF HEAVY PRECIPITATION FOR PARTS OF THE CENTRAL CONUS, THU-MON, JAN  
18-22.  
 
MODERATE RISK OF HEAVY PRECIPITATION FOR PARTS OF THE NORTH-CENTRAL CONUS,  
THU-MON, JAN 18-22.  
 
SEVERE DROUGHT FOR PARTS OF THE NORTHERN PLAINS, THE SOUTHWEST, THE CENTRAL AND  
SOUTHERN PLAINS, THE CENTRAL AND SOUTHERN MISSISSIPPI VALLEY, AND HAWAII.  
 
DETAILED SUMMARY  
 
FOR SATURDAY JANUARY 13 - WEDNESDAY JANUARY 17: LOW PRESSURE MOVING OVER THE  
NORTHERN MID-ATLANTIC JAN 13 IS EXPECTED TO MOVE INTO EASTERN CANADA BY JAN 14.  
HEAVY PRECIPITATION (SNOW, SLEET, FREEZING RAIN) IS ANTICIPATED FOR MUCH OF  
MAINE JAN 13. SNOWFALL AMOUNTS COULD EXCEED 6 INCHES IN 24 HOURS.  
 
AS THE AREA OF LOW PRESSURE MOVES INTO EASTERN CANADA, ARCTIC HIGH PRESSURE IS  
ANTICIPATED TO BUILD FROM THE PLAINS TO THE EASTERN U.S. JAN 13-15. A  
REINFORCING AREA OF ARCTIC HIGH PRESSURE IS FORECAST TO MOVE FROM THE NORTHERN  
PLAINS TO THE CENTRAL AND EASTERN CONUS JAN 15-17. THIS LEADS TO MUCH BELOW  
NORMAL TEMPERATURES FOR PARTS OF THE PLAINS, MISSISSIPPI VALLEY, GREAT LAKES,  
TENNESSEE AND OHIO VALLEYS, SOUTHEAST, AND APPALACHIANS JAN 13-17. NEGATIVE  
TEMPERATURE ANOMALIES EXCEEDING 20 DEGREES F ARE POSSIBLE FOR PARTS OF THESE  
REGIONS DURING THIS PERIOD.  
 
ABOVE NORMAL TEMPERATURES AND RAINFALL OVER EXISTING SNOW PACK, PRIOR TO THE  
START OF THE PERIOD LEAD TO FLOODING CONCERNS NEAR THE GREAT LAKES AND  
NORTHEAST. ICE JAMS MAY CONTRIBUTE TO RIVER FLOODING EARLY IN THE ASSESSMENT  
PERIOD.  
 
AREAS OF LOW PRESSURE ARE EXPECTED TO MOVE FROM THE ALEUTIANS INTO THE GULF OF  
ALASKA JAN 13-17. HEAVY PRECIPITATION (RAINFALL IN EXCESS OF 2 INCHES IN 24  
HOURS AT LOW ELEVATIONS, SNOWFALL IN EXCESS OF 8 INCHES IN 24 HOURS AT HIGHER  
ELEVATIONS) IS ANTICIPATED FOR PARTS OF THE SOUTH COAST OF MAINLAND ALASKA AND  
PARTS OF THE ALASKA PANHANDLE, JAN 13-14. PERIODS OF HIGH WINDS (JAN 13-15,  
SPEEDS IN EXCESS OF 40 KNOTS) AND SIGNIFICANT WAVES (JAN 13-16, HEIGHTS IN  
EXCESS OF 25 FEET) ARE FORECAST FOR PARTS OF SOUTH COASTAL MAINLAND ALASKA AND  
THE ALASKA PANHANDLE. A CHINOOK WIND EVENT IS EXPECTED FOR PARTS OF SOUTHERN  
ALASKA NEAR KODIAK ISLAND, ANCHORAGE, AND SOUTH OF THE ALASKA RANGE JAN 14-15.  
THIS LEADS TO MUCH ABOVE NORMAL TEMPERATURES (POSITIVE TEMPERATURE ANOMALIES  
EXCEEDING 25 DEGREES F) FOR PARTS OF THIS REGION THOSE DAYS.  
 
FOR THURSDAY JANUARY 18 - WEDNESDAY JANUARY 24: DURING WEEK-2, BOTH TEMPERATURE  
AND PRECIPITATION HAZARDS ARE FORECAST FOR PARTS OF THE CONUS. THE OVERALL  
CIRCULATION PATTERN IS EXPECTED TO BE PROGRESSIVE AND DEAMPLIFY AS THE DEEP  
TROUGH OVER THE EAST EARLY IN THE PERIOD WEAKENS AND TROUGH ENERGY OVER THE  
PACIFIC MOVES INLAND AND FLATTENS THE RIDGE FORECAST OVER THE WEST. THERE IS A  
SLIGHT RISK OF MUCH BELOW NORMAL TEMPERATURES FOR MUCH OF THE EASTERN THIRD OF  
THE CONUS JAN 18, AND A MODERATE RISK OF MUCH BELOW NORMAL TEMPERATURES FOR  
PARTS OF THE SOUTHEAST, MID-ATLANTIC, APPALACHIANS, OHIO VALLEY, GREAT LAKES  
AND NORTHEAST THE SAME DAY. THEREAFTER, A RAPID WARMING TO ABOVE NORMAL  
TEMPERATURES IS ANTICIPATED FOR THESE REGIONS DURING WEEK-2.  
 
WITH TROUGH ENERGY MOVING ONSHORE OVER THE WESTERN CONUS, AND AIR OF PACIFIC  
ORIGIN DOMINATING MOST OF THE COUNTRY, THERE IS A SLIGHT RISK OF HEAVY  
PRECIPITATION FOR MUCH OF THE WESTERN (JAN 18-20) AND EAST-CENTRAL (JAN 18-22)  
CONUS, A MODERATE RISK OF HEAVY PRECIPITATION FOR PARTS OF THE GREAT BASIN AND  
CENTRAL ROCKIES JAN 18-20, AND A HIGH RISK OF HEAVY PRECIPITATION FOR PARTS OF  
THE GREAT BASIN JAN 18-20. THERE IS ALSO A MODERATE RISK OF HEAVY PRECIPITATION  
FOR PARTS OF THE CENTRAL PLAINS AND MIDDLE AND UPPER MISSISSIPPI VALLEYS JAN  
18-22.  
 
THE U.S. DROUGHT MONITOR, VALID ON JANUARY 2, 2018 INDICATES AN INCREASE IN THE  
COVERAGE OF SEVERE TO EXCEPTIONAL DROUGHT (D2-D4) FROM 4.95% LAST WEEK TO 7.46%  
THIS WEEK. THE INCREASE PRIMARILY OCCURRED ACROSS THE SOUTHERN GREAT PLAINS AND  
THE SOUTHWESTERN U.S.  
 
FORECASTER: RANDY SCHECHTER  
 

 
 
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