PROGNOSTIC DISCUSSION FOR MONTHLY OUTLOOK
NWS CLIMATE PREDICTION CENTER COLLEGE PARK MD
300 PM EST TUE JAN 31 2017

30-DAY OUTLOOK DISCUSSION FOR FEBRUARY 2017

THE UPDATED TEMPERATURE AND PRECIPITATION OUTLOOKS FOR FEBRUARY 2017 ARE BASED 
LARGELY ON THE LATEST DYNAMICAL MODEL GUIDANCE (GFS, CFS, AND ECMWF), WPC'S 
WEEK-1 PRECIPITATION OUTLOOK, CPC'S WEEK-2 TEMPERATURE AND PRECIPITATION 
OUTLOOKS, THE 384-HR TOTAL PRECIPITATION FORECAST FROM THE LATEST GFS RUN 
(12Z), WEEK 3/4 TEMPERATURE AND PRECIPITATION FORECASTS FROM THE CFS AND ECMWF 
MODELS, POTENTIAL INFLUENCES OF THE MADDEN-JULIAN OSCILLATION (MJO), CURRENT 
SURFACE TEMPERATURE AND PRECIPITATION OBSERVATIONS, AND SEA SURFACE TEMPERATURE 
OBSERVATIONS ALONG THE U.S. COASTLINE.

THE UPDATED TEMPERATURE OUTLOOK FOR FEBRUARY 2017 FAVORS ABOVE-NORMAL AVERAGE 
TEMPERATURES ACROSS MOST OF THE CONTIGUOUS U.S., WITH THE EXCEPTION OF THE 
NORTHEAST AND NORTHERN AND EASTERN PORTIONS OF THE GREAT LAKES REGION, WHERE 
EQUAL CHANCES (EC) IS INDICATED. PROBABILITIES IN EXCESS OF 60-PERCENT ARE 
DEPICTED OVER THE SOUTHWEST. THE PREDICTION OF ABOVE-NORMAL TEMPERATURES IS 
BASED UPON CPC'S LATEST WEEK-2 TEMPERATURE GUIDANCE, AND THE MOST RECENT WEEK 
3/4 FORECASTS FROM THE CFS AND THE ECMWF MODELS. IT IS ALSO CONSISTENT WITH THE 
MOST RECENT RUNS OF THE MONTHLY CFS WHICH PREDICT WIDESPREAD ANOMALOUS WARMTH 
ACROSS THE CONUS. THE TEMPERATURE FORECAST FOR FEBRUARY IS MORE UNCERTAIN FOR 
ALASKA. BELOW-NORMAL MEAN TEMPERATURES ARE PROJECTED FOR ALASKA DURING THE 
WEEK-2 PERIOD, WITH A GRADUAL MODERATION IN TEMPERATURES EXPECTED DURING THE 
SECOND HALF OF FEBRUARY. THEREFORE, MOST OF THE STATE IS DEPICTED AS EC, WITH 
THE BEST CHANCE FOR ANY RESIDUAL AREA OF BELOW-NORMAL TEMPERATURES ANTICIPATED 
OVER SOUTHWESTERN PORTIONS OF THE STATE.

THE UPDATED PRECIPITATION OUTLOOK FOR FEBRUARY 2017 FAVORS ABOVE-MEDIAN 
PRECIPITATION FROM NORTHERN CALIFORNIA AND THE PACIFIC NORTHWEST GENERALLY 
EASTWARD ACROSS THE NORTHERN ROCKIES TO THE DAKOTAS, AND CONTINUING EASTWARD 
OVER THE UPPER MISSISSIPPI VALLEY, THE GREAT LAKES REGION, AND THE OHIO VALLEY. 
SOME OF THE WESTERN PRECIPITATION TOTALS PREDICTED DURING THE FIRST WEEK OF 
FEBRUARY WOULD BE ENOUGH TO CARRY THOSE AREAS FOR THE ENTIRE MONTH. ACCORDING 
TO THE ECMWF WEEK-1 TOTAL PRECIPITATION FORECAST, ABOUT 8-10 INCHES IS EXPECTED 
TO FALL (LIQUID EQUIVALENT) ACROSS OROGRAPHICALLY FAVORED AREAS OF NORTHERN 
CALIFORNIA (INCLUDING THE NORTHERN SIERRAS), AND SOUTHWESTERN OREGON DURING AN 
EXTENDED PERIOD OF ONSHORE FLOW. PROBABILITIES OF ABOVE-MEDIAN PRECIPITATION 
EXCEED 60-PERCENT FOR MUCH OF THE PACIFIC NORTHWEST. THE PREDICTED SWATH OF 
ABOVE-MEDIAN PRECIPITATION ACROSS MOST OF THE NORTHERN TIER OF THE CONTIGUOUS 
U.S. HAS ADDITIONAL SUPPORT FROM CPC'S WEEK-2 PRECIPITATION MAP, TODAY'S 12Z 
GFS 384-HR TOTAL PRECIPITATION GRAPHIC, AND THE WEEK 3/4 AND LATEST MONTHLY CFS 
PRECIPITATION FORECASTS. ANOTHER CONSIDERATION IS THE CURRENT STATUS OF THE 
MJO. THE ENHANCED CONVECTIVE PHASE OF THE MJO IS PRESENTLY OVER THE WESTERN 
MARITIME CONTINENT (PHASE 4), THOUGH THE SIGNAL IS WEAK. LAGGED COMPOSITES OF 
200-HPA HEIGHT (USING PHASE 4 IN THIS CASE) FOR THIS TIME OF YEAR FAVOR HEAVY 
PRECIPITATION ACROSS OREGON AND NORTHERN CALIFORNIA WITHIN THE FIRST WEEK OR SO 
OF FEBRUARY, FOLLOWED BY A DRYING TREND SHORTLY THEREAFTER. ELSEWHERE ACROSS 
THE CONUS, THE UPDATED 30-DAY PRECIPITATION OUTLOOK FAVORS BELOW-MEDIAN 
PRECIPITATION ACROSS MUCH OF THE SOUTHWEST, SOUTHERN ROCKIES, AND SOUTHERN 
PLAINS. THIS SIGNAL HAS BEEN CONSISTENTLY SUPPORTED BY AT LEAST THE LAST 9 RUNS 
OF THE CFS MONTHLY PRECIPITATION FORECASTS FOR FEBRUARY, THE LATEST WEEK-2 
PRECIPITATION OUTLOOK FROM CPC, AND THE MOST RECENT WEEK 3/4 PRECIPITATION 
OUTLOOKS FROM BOTH THE CFS AND ECMWF. CONFLICTING AND/OR MIXED CLIMATE GUIDANCE 
IS INDICATED FOR ALASKA; HENCE THE FORECAST OF EC FOR THE 49TH STATE.

------------------- PREVIOUS 30-DAY DISCUSSION FOLLOWS -------------------

THE FEBRUARY 2017 TEMPERATURE AND PRECIPITATION OUTLOOKS ARE BASED ON VARIOUS 
CLIMATE MODELS, STATISTICAL TOOLS, AND THE LIKELY STATES OF PATTERNS OF 
EXTRA-TROPICAL VARIABILITY. THE CURRENT LA NINA CONTINUES TO FADE, AND A 
TRANSITION TO NEUTRAL ENSO CONDITIONS IS EXPECTED BY FEBRUARY. CLIMATE SIGNALS 
ASSOCIATED WITH LA NINA WERE THEREFORE NOT LARGELY CONSIDERED.

THE MJO IS CURRENTLY ACTIVE, WITH THE ENHANCED CONVECTIVE PHASE OVER THE 
WESTERN HEMISPHERE AND AFRICA. DURING THE NEXT 2 WEEKS, THE ENHANCED PHASE IS 
ANTICIPATED TO PROGRESS EASTWARD INTO THE WESTERN (AND PERHAPS EASTERN) INDIAN 
OCEAN. THE INDIAN OCEAN DIPOLE (IOD) HAS BEEN PERSISTENT IN ITS NEGATIVE PHASE, 
WITH ENHANCED CONVECTION CONCENTRATED NEAR AND OVER THE MARITIME CONTINENT, AND 
GENERALLY SUPPRESSED CONVECTION OVER MOST OF THE INDIAN OCEAN AND WESTERN 
PACIFIC. MJO COMPOSITES (BASED ON THE EXPECTATION THAT THE ENHANCED PHASE OF 
THE MJO WILL REMAIN OVER THE INDIAN OCEAN) PROVIDE LITTLE GUIDANCE FOR THE U.S. 
TEMPERATURE AND PRECIPITATION OUTLOOKS FOR FEBRUARY.

THE TEMPERATURE OUTLOOK FOR FEBRUARY 2017 IS VERY UNCERTAIN, PRIMARILY DUE TO 
CONFLICTING DYNAMICAL AND STATISTICAL PREDICTIONS. THERE ARE ELEVATED CHANCES 
OF ABOVE-NORMAL TEMPERATURES FOR NEAR-COASTAL CALIFORNIA, AND ALONG THE FAR 
SOUTHERN BORDER STATES TO, AND INCLUDING, THE GULF COAST AND SOUTHERN ATLANTIC 
COAST STATES. ABOVE-NORMAL TEMPERATURES ARE ALSO FAVORED IN FEBRUARY FOR 
APPROXIMATELY THE WESTERN AND SOUTHERN HALVES OF ALASKA, PART OF WHICH IS DUE 
TO ABOVE-AVERAGE COASTAL SSTS. THE AREAS OF FAVORED ABOVE-NORMAL TEMPERATURES 
ARE GENERALLY SUPPORTED BY THE CALIBRATED AND UNCALIBRATED VERSIONS OF THE 
NMME, THE NCAR CLIMATE MODELS, THE CANADIAN MODELS, AND TO A LESSER EXTENT, THE 
IMME (INTERNATIONAL MULTI-MODEL ENSEMBLE), NASA, AND GFDL MODELS. EARLIER RUNS 
OF THE CFS MODEL (ABOUT 10 DAYS AGO) PREDICTED ABOVE-NORMAL TEMPERATURES FOR 
MOST OF THE CONTIGUOUS UNITED STATES, AND NORTHWESTERN PORTIONS OF ALASKA. 
SINCE THAT TIME, THE CFS HAS UNDERGONE SEVERAL TRANSITIONS. THE FIRST INVOLVED 
A RELATIVELY COLD PATTERN EAST OF THE ROCKIES, AND A RELATIVELY WARM PATTERN 
WEST OF THE ROCKIES. MOST RECENTLY, THE CFS FORECAST PATTERN HAS FLIPPED, 
FAVORING BELOW-NORMAL TEMPERATURES IN MUCH OF THE INTERIOR WEST, AND A RETURN 
TO ABOVE-NORMAL TEMPERATURES ACROSS THE EAST. THE FLUCTUATIONS OF THE CFS 
DURING THE PAST 10 DAYS SEEM TO SUGGEST A CIRCULATION PATTERN THAT HAS NOT YET 
LOCKED IN TO A STABLE SOLUTION. THESE FLUCTUATIONS IN THE CFS OUTPUT ARE ALSO 
LARGELY RESPONSIBLE FOR THE PREDOMINANCE OF EQUAL CHANCES (EC) ANTICIPATED IN 
THE TEMPERATURE PATTERN ACROSS THE CONUS. BELOW-NORMAL TEMPERATURES ARE FAVORED 
OVER THE NORTHERN PLAINS AND PORTIONS OF THE UPPER MISSISSIPPI VALLEY. THIS IS 
BASED ON SOME OF THE CFS MODEL RUNS, THE NCAR CLIMATE MODELS, AND TO A LESSER 
EXTENT, THE IMME. THIS AREA OF FAVORED BELOW-NORMAL TEMPERATURES IS ALSO 
SUPPORTED BY THE PRESENCE OF DEEP SNOW COVER.

THE PRECIPITATION OUTLOOK FOR FEBRUARY 2017 IS ALSO FAIRLY UNCERTAIN, MOSTLY 
DUE TO CONFLICTING DYNAMICAL AND STATISTICAL MODEL SOLUTIONS. ODDS FOR 
ABOVE-MEDIAN PRECIPITATION ARE ENHANCED ACROSS THE NORTHERN PLAINS, AND FROM 
ABOUT ILLINOIS AND INDIANA NORTHEASTWARD ACROSS THE CENTRAL AND EASTERN GREAT 
LAKES REGION, AND NORTHERN NEW ENGLAND. THESE TWO AREAS OF FAVORED ABOVE-MEDIAN 
PRECIPITATION ARE SUPPORTED BY RECENT RUNS (ABOUT PAST 8-10 DAYS) OF THE 
PROBABILISTIC CFS, AND TO SOME EXTENT, THE NMME, AND THE NASA MODEL. 
BELOW-MEDIAN PRECIPITATION IS FAVORED ACROSS CALIFORNIA, MOST OF NEVADA, 
ARIZONA, NEW MEXICO, MOST OF THE SOUTHERN PLAINS, AND ACROSS GEORGIA AND THE 
CAROLINAS. THIS IS BASED PRIMARILY ON THE CFS, WITH LESSER CONTRIBUTIONS FROM 
THE SMLR, CCA, AND THE OCN. THE CALIBRATED AND UNCALIBRATED NMME SOLUTIONS 
SUPPORT RELATIVE DRYNESS OVER PORTIONS OF THE SOUTHEAST, AS DO THE CANADIAN 
CANCM4 MODEL, NCAR, AND NASA GEOS5 RUNS.


FORECASTER: ANTHONY ARTUSA


THE CLIMATIC NORMALS ARE BASED ON CONDITIONS BETWEEN 1981 AND 2010, FOLLOWING
THE WORLD METEOROLOGICAL ORGANIZATION CONVENTION OF USING THE MOST RECENT 3 
COMPLETE DECADES AS THE CLIMATE REFERENCE PERIOD.  THE PROBABILITY ANOMALIES
FOR TEMPERATURE AND PRECIPITATION BASED ON THESE NEW NORMALS BETTER REPRESENT
SHORTER TERM CLIMATIC ANOMALIES THAN THE FORECASTS BASED ON OLDER NORMALS.



THE NEXT MONTHLY OUTLOOK...FOR MAR ... WILL BE ISSUED ON THU FEB 16 2017


THESE OUTLOOKS ARE BASED ON DEPARTURES FROM THE 1981-2010 BASE PERIOD.

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