Threats Assessment Discussion

416 
FXUS21 KWNC 151851
PMDTHR
US HAZARDS OUTLOOK
NWS CLIMATE PREDICTION CENTER COLLEGE PARK MD
300 PM EDT OCTOBER 15 2013
SYNOPSIS: A RELATIVELY TRANQUIL WEATHER PATTERN IS ANTICIPATED OVER MOST OF THE 
CONUS. A  COLD FRONT IS FORECAST TO STALL ALONG THE GULF COAST/NORTHERN GULF OF 
MEXICO. HIGH PRESSURE IS EXPECTED TO DOMINATE MOST OF THE LOWER 48 STATES. AN 
AREA OF DEEP LOW PRESSURE IS FORECAST OVER THE BERING SEA. THIS SYSTEM IS 
EXPECTED TO DRIFT SLOWLY EASTWARD AND WEAKEN.
HAZARDS
HEAVY RAIN FOR PARTS OF SOUTHEAST TEXAS, THE LOWER MISSISSIPPI VALLEY, AND 
SOUTHEAST, FRI-SAT, OCT 18-19.
HEAVY RAIN FOR PARTS OF SOUTHERN TEXAS, FRI-MON, OCT 18-21.
HEAVY RAIN FOR PARTS OF THE EASTERN ALEUTIANS, SOUTH-COASTAL ALASKA, AND THE 
ALASKAN PANHANDLE, FRI-SUN, OCT 18-20.
HIGH WINDS FOR PARTS OF THE ALEUTIANS, SOUTH-COASTAL ALASKA, WEST-COASTAL 
ALASKA, AND THE ALASKAN PANHANDLE, FRI-SUN, OCT 18-20. 
SIGNIFICANT WAVES FOR PARTS OF THE ALEUTIANS, FRI-SAT, OCT 18-19.
FLOODING OCCURRING OR IMMINENT FOR PARTS OF SOUTH-CENTRAL TEXAS, FRI-SAT, OCT 
18-19.
FLOODING LIKELY FOR PARTS OF THE NORTHERN PLAINS, FRI-SUN, OCT 18-20.
SEVERE DROUGHT FOR PARTS OF THE MIDWEST, LOWER MISSISSIPPI VALLEY, GREAT 
PLAINS, RIO GRANDE VALLEY, ROCKIES, SOUTHWEST, GREAT BASIN, CALIFORNIA, AND 
HAWAII.
DETAILED SUMMARY
FOR FRIDAY OCTOBER 18 - TUESDAY OCTOBER 22: A RELATIVELY QUIET WEATHER PATTERN 
IS ANTICIPATED ACROSS THE CONUS. ANTECEDENT RAINFALL LEADS TO ONGOING OR 
POSSIBLE FLOODING FOR PARTS OF SOUTH-CENTRAL TEXAS, AND LIKELY FLOODING FOR 
PARTS OF THE NORTHERN PLAINS. SOME MINOR FLOODING IS ALSO POSSIBLE FOR PORTIONS 
OF THE RED RIVER OF THE NORTH ALTHOUGH A HAZARD AREA IS NOT CURRENTLY INDICATED.
A FRONTAL SYSTEM IS FORECAST TO STALL ALONG THE GULF COAST/NORTHERN GULF OF 
MEXICO. THIS FRONT WILL ACT AS A FOCUSING MECHANISM FOR PRECIPITATION AND IS 
EXPECTED TO LEAD TO HEAVY RAIN FOR PARTS OF SOUTHEAST TEXAS, THE LOWER 
MISSISSIPPI VALLEY, AND SOUTHEAST, FRI-SAT, OCT 18-19, AND FOR SOUTHERN TEXAS 
FRI-MON, OCT 18-21.
DEEP LOW PRESSURE OVER THE BERING SEA IS FORECAST TO LEAD TO STRONG SURFACE 
SOUTHERLY FLOW OVER PARTS OF SOUTH-COASTAL ALASKA, THE ALASKAN PANHANDLE, AND 
PARTS OF THE ALEUTIANS. THIS IS EXPECTED TO CAUSE HIGH WINDS FOR PARTS OF THE 
ALEUTIANS, SOUTH-COASTAL ALASKA, WEST COASTAL ALASKA, AND THE ALASKAN PANHANDLE 
FRI-SUN, OCT 18-20. THIS AREA OF LOW PRESSURE IS ALSO FORECAST TO BRING HEAVY 
RAIN TO PARTS OF THE EASTERN ALEUTIANS, SOUTH-COASTAL ALASKA AND THE ALASKAN 
PANHANDLE, THU-SUN, OCT 18-20. SIGNIFICANT WAVES ARE ANTICIPATED FOR PARTS OF 
THE ALEUTIANS, FRI-SAT, OCT 18-19.
FOR WEDNESDAY OCTOBER 23 - TUESDAY OCTOBER 29: MODEL GUIDANCE HAS TRENDED 
TOWARDS A HIGHLY AMPLIFIED FLOW DEVELOPING ACROSS THE NORTHEAST PACIFIC AND 
NORTH AMERICA DURING THE LATTER PART OF OCTOBER. AN UPPER-LEVEL TROUGH IS 
ANTICIPATED OVER THE EASTERN THREE-QUARTERS OF THE CONUS WHILE AN UPPER-LEVEL 
RIDGE IS FORECAST OVER THE FAR EASTERN PACIFIC. COOLER THAN NORMAL TEMPERATURES 
ARE EXPECTED OVER MUCH OF THE CENTRAL AND EASTERN CONUS BUT MODEL UNCERTAINTY 
PRECLUDES THE SPECIFICATION OF A HAZARD AREA AT THE CURRENT TIME.
A TROUGH IS EXPECTED TO PERSIST OVER THE ALEUTIANS LEADING TO A CONTINUATION OF 
UNSETTLED WEATHER FOR MUCH OF ALASKA BUT NO HAZARDS CAN RELIABLY BE SPECIFIED.
ACCORDING TO THE U.S. DROUGHT MONITOR VALID OCTOBER 8, THE SPATIAL COVERAGE OF 
SEVERE TO EXCEPTIONAL DROUGHT (D2-D4 DESIGNATION) DECREASED OVER ONE PERCENT, 
FROM 20.70 TO 19.60 PERCENT OF THE CONTIGUOUS U.S. THE LARGES IMPROVEMENTS 
OCCURRED ACROSS WYOMING, NEBRASKA, AND THE LOWER MISSISSIPPI VALLEY.
FORECASTER: RANDY SCHECHTER 
$$