067  
FXUS01 KWBC 012001  
PMDSPD  
 
SHORT RANGE FORECAST DISCUSSION  
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD  
300 PM EST TUE JAN 01 2019  
 
VALID 00Z WED JAN 02 2019 - 00Z FRI JAN 04 2019  
 
...NEW WINTER STORM TO DEVELOP OVER THE SOUTHWEST AND EJECT EAST  
ACROSS THE SOUTHERN PLAINS...  
 
...HEAVY RAIN AND THE POTENTIAL FOR FLASH FLOODING WILL EXIST  
ACROSS EASTERN TEXAS, THE LOWER MISSISSIPPI VALLEY AND MID-SOUTH...  
 
A NEW STORM SYSTEM WILL GRADUALLY BE DEVELOPING OVER THE SOUTHWEST  
BY WEDNESDAY AND WILL THEN EJECT OFF TO THE EAST AND IMPACT A  
LARGE AREA OF THE SOUTHERN PLAINS AND THE LOWER MISSISSIPPI VALLEY  
GOING THROUGH THURSDAY. MULTIPLE HAZARDS ARE EXPECTED WITH THIS  
SYSTEM WHICH WILL INITIALLY INCLUDE HEAVY SNOW OVER AREAS OF  
EASTERN ARIZONA AND SOUTHWEST NEW MEXICO GOING THROUGH WEDNESDAY  
EVENING WHERE LOCALLY AS MUCH AS 6 INCHES OF SNOWFALL IS EXPECTED.  
DOWNSTREAM ACROSS AREAS OF CENTRAL AND NORTHERN TEXAS, AND ALSO  
SOUTHERN OKLAHOMA, THERE WILL BE A SHALLOW LAYER OF SUBFREEZING  
TEMPERATURES THAT WILL BE CONDUCIVE FOR SOME FREEZING RAIN AS  
MOISTURE AND ENERGY BEGINS TO ARRIVE FROM THE SOUTHERN HIGH  
PLAINS. BY WEDNESDAY NIGHT AND THURSDAY, A MORE SUBSTANTIAL AXIS  
OF SNOW AND ALSO FREEZING RAIN WILL TEND TO FOCUS OUT ACROSS AREAS  
OF NORTHERN AND WESTERN TEXAS AND ALSO MUCH OF CENTRAL AND  
SOUTHWEST OKLAHOMA WITH SEVERAL INCHES OF ACCUMULATING SNOW AND  
CONCERNS OF A COATING OF ICE. TRAVEL CONDITIONS ARE LIKELY TO  
BECOME HAZARDOUS AS A RESULT. THE COLD AIR THAT WILL FACILITATE  
THE WINTER WEATHER CONCERNS WILL BE DRIVEN BY HIGH PRESSURE  
INITIALLY OUT OVER THE CENTRAL PLAINS, AND WILL RESULT IN HIGH  
TEMPERATURES THAT WILL BE AS MUCH AS 10 TO 20 DEGREES BELOW NORMAL  
FROM THE SOUTHWEST EAST OUT ACROSS THE SOUTHERN PLAINS FOR THE  
NEXT COUPLE OF DAYS.  
 
MEANWHILE, AS CONCERNS FOR SNOW AND ICE EVOLVE OUT ACROSS THE  
SOUTHWEST AND SOUTHERN PLAINS REGION, THERE WILL BE AN  
INCREASINGLY STRONG TRANSPORT OF MOISTURE TO THE NORTH OUT OF THE  
WESTERN GULF OF MEXICO AS A WAVE OF LOW PRESSURE DEVELOPS ALONG A  
FRONTAL ZONE OFFSHORE THE TEXAS COASTLINE. THIS WILL RESULT IN A  
WIDESPREAD AREA OF RAIN WITH PERHAPS SOME EMBEDDED THUNDERSTORMS  
IMPACTING INITIALLY EASTERN TEXAS BY WEDNESDAY AFTERNOON AND  
EVENING, BUT THEN ADVANCING EAST ACROSS THE LOWER MISSISSIPPI  
VALLEY WEDNESDAY NIGHT AND ACROSS PORTIONS OF THE MID-SOUTH  
THROUGH THURSDAY. SOME OF THE RAIN IS EXPECTED TO BE HEAVY WITH  
STORM TOTALS OF AS MUCH AS 2 TO 4 INCHES EXPECTED AND LOCALIZED  
AMOUNTS POSSIBLY EXCEEDING 5 INCHES WHERE HEAVY RAINFALL AND  
THUNDERSTORMS TRAIN OVER THE SAME AREA. GIVEN THE WET ANTECEDENT  
CONDITIONS ALREADY FROM RECENT HEAVY RAINFALL, THERE WILL BE AN  
ELEVATED CONCERN FOR FLASH FLOODING AND RUNOFF PROBLEMS. THE  
WEATHER PREDICTION CENTER AS A RESULT HAS HIGHLIGHTED A SLIGHT  
RISK OF EXCESSIVE RAINFALL ACROSS THIS REGION.  
 
ELSEWHERE, A SYSTEM OVER THE PACIFIC OCEAN WILL APPROACH THE  
PACIFIC NORTHWEST BY THURSDAY AND ALLOW A COLD FRONT TO CROSS THE  
COASTAL RANGES AND MOVE INLAND. HEAVY RAIN WITH AN EMPHASIS ON  
WESTERN WASHINGTON CAN BE EXPECTED, AND SOME AREAS OF THE OLYMPIC  
PENINSULA WILL SEE AS MUCH AS 3 TO 5 INCHES OF RAIN BY THURSDAY  
EVENING. THIS SURGE OF PACIFIC MOISTURE WILL ALSO ALLOW HEAVY  
PRECIPITATION TO REACH INTO THE NORTHERN WASHINGTON CASCADES WHERE  
IT WILL BE COLD ENOUGH FOR HEAVY ACCUMULATING SNOWFALL FOR THE  
HIGHEST PEAKS. IN FACT, LOCALLY AS MUCH AS 1 TO 2 FEET OF NEW SNOW  
WILL BE POSSIBLE FOR THIS AREA. IN TERMS OF TEMPERATURES, THE  
PACIFIC NORTHWEST WILL BE NEAR TO SLIGHTLY ABOVE NORMAL, BUT  
EXPECT AREAS DOWNSTREAM ACROSS THE NORTHERN PLAINS BY THURSDAY TO  
SEE PLENTY OF WARM, DOWNSLOPING WINDS THAT WILL PROMOTE HIGH  
TEMPERATURES OF AS MUCH AS 15 TO 25 DEGREES ABOVE NORMAL.  
 
ORRISON  
 
GRAPHICS AVAILABLE AT  
WWW.WPC.NCEP.NOAA.GOV/BASICWX/BASICWX_NDFD.PHP  

 
 
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