PROGNOSTIC DISCUSSION FOR MONTHLY OUTLOOK NWS CLIMATE PREDICTION CENTER CAMP SPRINGS MD 300 PM EST FRI MAR 31 2006 30-DAY OUTLOOK DISCUSSION FOR APRIL 2006 THE OCEANIC AND ATMOSPHERIC INDICATORS FOR THE TROPICAL PACIFIC OCEAN REMAIN CONSISTENT WITH WEAK LA NINA CONDITIONS. SEA SURFACE TEMPERATURES DURING MID-MARCH REMAINED BELOW NORMAL ACROSS THE EQUATORIAL PACIFIC BETWEEN THE DATE LINE AND 90W. ABOVE NORMAL SSTS WERE CONFINED TO THE EXTREME WESTERN PACIFIC AND THE EXTREME EASTERN PACIFIC BETWEEN NEAR THE SOUTH AMERICAN COAST. AT DEPTH OCEAN TEMPERATURES REMAINED BELOW NORMAL ACROSS THE EASTERN AND CENTRAL PACIFIC AND ABOVE NORMAL IN THE WESTERN PACIFIC. THE PATTERN OF OLR ACROSS THE CENTRAL AND WESTERN TROPICAL PACIFIC HAS BEEN CONSISTENT WITH LA NINA CONDITIONS SINCE NOVEMBER... WITH ENHANCED CONVECTION CONFINED TO INDONESIA AND THE WESTERN PACIFIC AND SUPPRESSED CONVECTION DOMINATING THE CENTRAL PACIFIC. DURING MARCH ENHANCED CONVECTION SHIFTED WESTWARD AND WAS CENTERED OVER THE INDIAN OCEAN AND INDONESIA. STRONGER-THAN-AVERAGE LOW LEVEL EASTERLY WINDS HAVE ALSO BEEN OBSERVED ACROSS THE CENTRAL AND WESTERN EQUATORIAL PACIFIC SINCE NOVEMBER. THESE OCEANIC AND ATMOSPHERIC FEATURES ARE ALL CONSISTENT WITH ONGOING LA NINA CONDITIONS AND ARE EXPECTED TO PERSIST AT LEAST THROUGH THE MONTH OF APRIL. THE TEMPERATURE OUTLOOK FOR APRIL IS BASED ON THE TRADITIONAL STATISTICAL TOOLS... CCA...SMLR... AND OCN... THE CFS.. AND INOUT FROM DYNAMICAL MODELS FOR THE FIRST TWO WEEKS OF THE MONTH. THE STATISTICAL TOOLS ALL HAVE INDICATIONS OF ABOVE NORMAL TEMPERATURES TO VARYING DEGREES IN THE SOUTHWESTERN PART OF THE NATION... WITH THE OCN HAVING THE STRONGEST SIGNAL AND THE SMLR PROVIDING THE WEAKEST FORECAST. INDICATIONS FROM THE STATISTICAL TOOLS ARE MORE MIXED IN THE PACIFIC NORTHWEST... WITH THE OCN PREDICTING NEAR NORMAL TEMPERATURES AND THE CCA PREDICTING BELOW NORMAL. THE UPDATED CFS FORECASTS ABOVE NORMAL TEMPERATURES IN THE SOUTHWEST EXTENDING EASTWARD TO TEXAS AND OKLAHOMA. IT ALSO HAS WEAK INDICATIONS OF BELOW NORMAL TEMPERATURES IN THE NORTHWEST. INDICATIONS FROM THE STATISTICAL TOOLS ARE WEAKER OVER THE EASTERN PART OF THE CONUS... WITH NO TOOLS INDICATING STATISTICALLY SIGNIFICANT TEMPERATURE DEPARTURES ANYWHERE. THE SHORTER TERM GUIDANCE FAVORS ABOVE NORMAL TEMPERATURES ACROSS MUCH OF THE EASTERN TWO THIRDS OF THE NATION WITH BELOW NORMAL TEMPERATURES ALONG THE WEST COAST. BLENDING THE SHORT RANGE AND LONGE RANGE INDICATIONS RESULTS IN A FORECAST OF BELOW NORMAL IN THE PACIFIC NORTHWEST AND ABOVE NORMAL NORMAL ACROSS MUCH OF THE SOUTHERN AND CNETRAL PLAINS AND THE SOUTHEAST. THE SOUTHWEST HAS BEEN LEFT AS EC WITH CONFLICTING SIGNALS BETWEEN THE LONG RANGE AND SHORT RANGE INDICATORS. THE TOOLS ARE ALSO MIXED FOR ALASKA... WITH THE OCN AND CCA HAVING LIMITED INDICATIONS FOR BELOW NORMAL TEMPERATURES AND THE SMLR PREDICITNG ABOVE NORMAL TEMPERATURES... PARTICULARLY IN THE WEST AND IN THE PANHANDLE. THE SHORT RANGE INDICATORS FOR ALASKA ARE ALSO NOT PROVIDING A STRONG SIGNAL. THE PRECIPITATION FORECAST FOR THE LOWER 48 STATES AND ALASKA IS BASED ON STATISTICALLY SIGNIFICANT FORECASTS FROM THE CFS COMBINED WITH INDICATIONS FROM THE EARLY PART OF THE MONTH. THE STATISTICAL TOOLS... AS IS TYPICALLY THE CASE FOR THE MONTHLY FORECAST... HAVE NO STATISTICALLY SIGNIFICANT COHERENT REGIONS INDICATED FOR EITHER ABOVE OR BELOW NORMAL PRECIPITATION. THE CFS SHOWED A TYPICAL LA NINA PATTERN... WITH DRY CONDITIONS ACROSS THE SOUTH AND WET CONDITIONS ACROSS THE PACIFIC NORTHWEST... THE NORTHERN PLAINS... AND THE TENNESSEE VALLEY. THE SHORT RANGE GUIDANCE FAVORS WET CONDITIONS IN THE NORTHERN PLAINS AND DRY IN THE SOUTHEAST. THE SHORT RANGE GUIDANCE ALSO HAS WET CONDITIONS IN CALIFORNIA AND NEVADA WHICH SHOULD RESULT IN WET CONDITIONS FOR THE MONTH. THE MOST PROBLEMATIC REGION WAS THE MID-ATLANTIC AND NORTHEAST... WHERE DROUGHT HAS BEEN EXPANDING. EARLY MONTH INDICATIONS FAVOR ABOVE NORMAL RAINFALL IN THE NORTHEAST AND NEAR NORMAL IN THE MID-ATLANTIC. WEEK 2 INDICATIONS WEAKLY FAVOR DRIER THAN NORMAL CONDITIONS IN THE MID-ATLANTIC. EC WAS FORECAST IN THE SOUTHWEST SINCE NORMAL APRIL VALUES ARE GENERALLY LESS THAN ONE INCH IN MOST LOCATIONS. THERE WERE NO STATISTICALLY SIGNICANT SIGNALS FOR ALASKA. FORECASTER: M. HALPERT NOTES - AREAS OF UNCERTAINTY THAT FORMERLY WERE LABELED CL (CLIMATOLOGICAL PROBABILITIES) ARE NOW LABELED EC (EQUAL CHANCES). THE NEXT MONTHLY OUTLOOK... FOR MAY 2006... WILL BE ISSUED ON THU APR 20 2006 THESE OUTLOOKS ARE BASED ON DEPARTURES FROM THE 1971-2000 BASE PERIOD. $$