197
FXUS01 KWBC 200747
PMDSPD
SHORT RANGE FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
246 AM EST WED DEC 20 2023
VALID 12Z WED DEC 20 2023 - 12Z FRI DEC 22 2023
...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL OVER PARTS OF
SOUTHERN CALIFORNIA ON WEDNESDAY AND THURSDAY...
..RAIN FOR MOST OF CALIFORNIA
...TEMPERATURES WILL BE 15 TO 25 DEGREES ABOVE AVERAGE OVER PARTS
OF THE NORTHERN/CENTRAL HIGH PLAINS...
AN UPPER-LEVEL OFF THE CALIFORNIA COAST WILL SLOWLY MOVE SOUTHWARD
OVER THE PACIFIC BEFORE MOVING INLAND OVER NORTHWESTERN MEXICO BY
SATURDAY. THE LOW WILL STREAM MOISTURE INTO CALIFORNIA, CREATING
RAIN AND ISOLATED HIGHEST-ELEVATION SNOW OVER THE SIERRA NEVADA
MOUNTAINS. THE STORM WILL PRODUCE HEAVY RAIN OVER MUCH OF COASTAL
CALIFORNIA AND INLAND. THEREFORE, THE WPC HAS ISSUED A MODERATE
RISK OF EXCESSIVE RAINFALL OVER PARTS OF SOUTHERN CALIFORNIA
THROUGH THURSDAY MORNING. THE ASSOCIATED HEAVY RAIN WILL CREATE
NUMEROUS AREAS OF FLASH FLOODING WITH NARROW CANYONS/GULLIES AND
BURN SCARS THE MOST VULNERABLE. FURTHERMORE, MANY STREAMS MAY
FLOOD, POTENTIALLY AFFECTING LARGER RIVERS.
ON THURSDAY, THE THREAT OF EXCESSIVE RAINFALL CONTINUES AS A PLUME
OF MOISTURE STREAMS INTO SOUTHERN CALIFORNIA. THEREFORE, THE WPC
HAS ISSUED A MODERATE RISK OF EXCESSIVE RAINFALL OVER PARTS OF
SOUTHERN CALIFORNIA FROM THURSDAY INTO FRIDAY MORNING. THE
ASSOCIATED HEAVY RAIN WILL CREATE NUMEROUS AREAS OF FLASH FLOODING
WITH NARROW CANYONS/GULLIES AND BURN SCARS THE MOST VULNERABLE.
FURTHERMORE, MANY STREAMS MAY FLOOD, POTENTIALLY AFFECTING LARGER
RIVERS.
HOWEVER, THE RAIN OVER NORTHERN CALIFORNIA WILL END ON THURSDAY.
MOREOVER, LIGHTER RAINFALL WILL FALL OVER PARTS OF THE SOUTHWEST
AND SOUTHERN ROCKIES THROUGH WEDNESDAY NIGHT.
MEANWHILE, WEAK UPPER-LEVEL RIDGING AND DOWNSLOPE WIND WILL
PRODUCE TEMPERATURES 15 TO 25 DEGREES ABOVE AVERAGE OVER PARTS OF
THE NORTHERN/CENTRAL HIGH PLAINS. ELSEWHERE, THE CIRCULATION
AROUND THE AREA OF HIGH PRESSURE OVER THE SOUTHEAST/MID-ATLANTIC
WILL PRODUCE RETURN FLOW OFF THE GULF OF MEXICO THAT WILL SLOWLY
MOISTEN THE AIR OVER THE CENTRAL/SOUTHERN PLAINS NORTHWARD TO THE
GREAT LAKES. LIGHT RAIN WILL DEVELOP OVER PARTS OF THE WESTERN
GULF COAST ON WEDNESDAY AFTERNOON, SLOWLY EXPANDING NORTHWARD OVER
THE CENTRAL/SOUTHERN PLAINS BY THURSDAY EVENING. OVERNIGHT
THURSDAY INTO FRIDAY, THE RAIN WILL MOVE/EXPAND INTO PARTS OF THE
MIDDLE/LOWER MISSISSIPPI VALLEY AND PARTS OF THE GREAT LAKES.
ZIEGENFELDER
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HTTPS://WWW.WPC.NCEP.NOAA.GOV/BASICWX/BASICWX_NDFD.PHP
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