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SPRING 2013 and SUMMER 2013 CONUS. WHAT HAS THE WINTER BEEN LIKE?. CLOSE TO NORMAL TEMPS. 125-300% ABOVE NORMAL OVER ALL OF THE MIDWEST… 75-150% OVER PLAINS.. Mainly eastern Plains NORTH of TX.
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WHAT HAS THE WINTER BEEN LIKE? CLOSE TO NORMAL TEMPS
125-300% ABOVE NORMAL OVER ALL OF THE MIDWEST… 75-150% OVER PLAINS.. Mainly eastern Plains NORTH of TX
LAST 30 DAYS 2 BIG WINTER STORMS OVER LOWER & CENTRAL PLAINS & WCB HAVE BROUGHT LARGE AREAS OF 125-400% ABOVE NORMAL MADDEN JULIAN OSCILLATION
IS SEASONAL FORECASTING JUST GLORIFIED GUESSING? In the OLD days ( 1960s..1970s..1980s) that was pretty much the case. Professional Meteorologists were using MOON PHASES to make seasonal forecast (Harris Mann). Since the Mid 1990s a lot of progress has been made at 30 day forecasts and out to 120 days . WHAT HAS CHANGED ? Much Improved Climate Models Better understanding of Atmospheric patterns Better understanding impact of Sea Surface temps ANALOG methods
SEA SURFACE TEMPS Research shows that large areas of COLD and WARM SSTAs (Sea Surface Temperature Anomalies) that stay in one general location can and DO affect weather patterns • EL NINO • LA NINA • LA NADA • PDO • AMO? ENSO
ENSO REGIONS ENSO REGION 3.4 IS THE BIG ONE… WARM SSTAs in 3.4= EL NINO… COLD SSTAs = LA NINA
AS OF EARLY MARCH ENSO REGION 3.4 WAS “ NEUTRAL” or “la nada “ STRONG EL NIN0 MOD EL NINO WEAK EL NIN0 WEAK LA NINA MOD LA NINA STRONG LA NINA
EL NINO or LA NINA EVENTS COME “ UP” FROM THE SUB SURFACE SO BY LOOKING DEEP INTO THE EQUATORIAL WATERS WE CAN SEE IF EL NINO OR LA NINA IS DEVELOPING OR WEAKENING WARM WATER COLD WATER
SINCE FEB 19… THE POOL OF COLD WATER HAS WEAKEND CONSIDERABLY… BUT SO HAS THE WARM POOL. THUS “ LA NADA“ OR NEUTRAL ENSO CONDITIONS ARE LIKELY THRU AT LEAST MAY 2013.
LETS LOOK AT SOME COMPUTER MODEL FORECASTS FOR THE ENSO TO SEE IF THERE ARE ANY INDICATIONS OF EL NINO or LA NINA EVENTS LATER THIS SPRING / SUMMER 2013 This is the European ENSEMBLE Model. The Numerous red lines show slow rise in ENSO region 3.4 to NEUTRAL conditions in SPRING and POSSIBLE WEAK EL NINO conditions in Summer 2013
This is the CFS ENSEMBLE Model … from CPC (Climate Prediction Center) . This Model and its forecasts carries lot of weight with many Grain Meteorologists in making their Spring & Summer forecasts. The CFS shows NEUTRAL conditions “LA NADA” right through OCT 2013.
This is a SUMMARY of 25 different ENSO computer models run from Mid FEB to NOV 2013. The vast MAJORITY shows NEUTRAL conditions thru the Summer
ENSO EVENTS (La Nina or El Nino) ARE ONE OF SEVERAL VERY IMPORTANT / CRITICAL SEAS SURFACE TEMPERATURE PATTERNS AROUND THE GLOBE THAN CAN … AND DO ..HAVE MAJOR IMPACTS ON WEATHER PATTERNS IN N. AMERICA… CHINA… INDIA ...AUSTRALIA … and EUROPE. For North America ..since MOST of the weather patterns move in a general West to East Direction… large pools of WARM or COLD SSTAs (Sea Surface Temperature Anomalies) directly IMPACT weather patterns in the USA and Canada.
THE PDO POSITIVE PDO (+PDO) features WARM SSTAs along WEST coast of N. America& COLD water in Central Pacific NEGATIVE PDO (-PDO) features COLD SSTAs along WEST coast of N. America & WARM waters in central Pacific -PDO +PDO
LAST WINTER PATTERN exampleJULY 2009
EXAMPLES 2012 1998
This map shows CURRENT SSTAs around the World. I have highlighted the huge pool of COLD WATERS in the eastern & Northern Pacific Ocean This is a TEXTBOOK Case of a -PDO
OK… so now we know that moderate and strong -PDO and +PDO values have big impact on SPRING and SUMMER weather patterns over North America. What can that tell us about SPRING and SUMMER 2013 in USA and southern CANADA ? THE ANALOG METHOD OF SEASONAL FORECASTING
HOW and WHY DOES ANALOG SEASONAL FORECASTING WORK? • Certain atmospheric conditions cause some weather patterns to occur more often than others. • The KEY is focus on the correct parameters. For example if you think the upcoming Summer is will be influenced by XYZ... but if XYZ does not show your seasonal forecast is going to bust. • Look at SUMMER 2012 … It was ASSUMED by most seasonal forecasters that the El Nino would Kick in at SOME point and turn the pattern wetter and cooler over the Midwest and Plains. But as we know now El Nino pattern never developed • Requires CONSTANT monitoring as sometimes the specific atmospheric condition (El Nino PDO AMO etc) can collapse or suddenly turn much stronger
GOING into SPRING OF 2013… the current MODERATE -PDO Values are EXPECTED to continue. ModeratelyNEGATIVE PDO Rainfall MAM WET DRY
IF THE -PDO GETS STRONGER IN SUMMER 2013 (the Cold water in eastern North Pacific gets colder) *** SUMMER OF 2012 Featured very strong NEGATIVE PDO *** DRY Above & Much AboveTemps DRY
QBO data goes back to mid 1950s. It is essentially a SINE wave. When the QBO value is negative (blowing from west to east) it tends to support certain Types of weather patterns…when it is POSITIVE the QBO tends to support different weather patterns
QBO RAINFALL ANALOGS WETTER THAN NORMAL OVER MO & LOWER MIDWEST
QBO TEMPERATURE ANALOGS FOR SPRING QBO DOES NOT GIVE A “SIGNAL” OR INDICATION OF BELOW OR ABOVE NORMAL TEMPS
CFS CLIMATE MODELS APRIL 2013 RAINFALL ** FORECAST ** BASED ON CFS IN EARLY MARCH APRIL 2013 LOOKS VERY DRYOVER MIDWEST
MAY 2013 RAINFALL ** FORECAST ** BASED ON CFS IN EARLY MARCH MAY 2013 LOOKS DRY OVER GULF COAST NORMAL OVER MIDWEST
MAY 2013 TEMP ** FORECAST ** BASED ON CFS IN EARLY MARCH MAY 2013 SHOWS NEAR NORMAL TEMPS
JUNE 2013 RAINFALL ** FORECAST ** BASED ON CFS IN EARLY MARCH JUNE 2013 LOOKS VERY WET OVER CENTRAL PLAINS & THE MIDWEST
JUNE 2013 TEMP ** FORECAST ** BASED ON CFS IN EARLY MARCH MAY 2013 HAS NEAR NORMAL TEMPS OVER MOST OF USA
SUMMARY • NO EL NINO or LA NINE THROUGH END OF MAY 2013 • This means that OTHER atmospheric features will drive the Pattern • HUGE DROUGHT AREA OVER PLAINS & MIDWEST is the KEY ISSUE… How fast the drought area will “ shrink” ..if it does …will be the BIIIIIG issue SPRING & Early Summer. • If the Drought area does NOT shrink / weaken by MAY 30 hard to see a “ normal” Summer for 2013… for all of Plains and Midwest • EAST OF THE MISSISSIPPI RIVER… Soil Moisture is IDEAL (in some places it is “too darn wet”). Chilly & Wet March & early APRIL… lead to talk of Planting delays
RELATIVE WEAK QBO VALUES FAVOR STRONG BLOCKING PATTERNS OVER N. AMERICA ALL SPRING • This means COLDER than Normal temps and WETTER than Normal… MAINLY East of the Mississippi River • BLOCKING PATTERNS COMBINED WITH -PDO FEATURE… DOES **NOT** FAVOR MODERATE or SIGNIFICANT RAINS IN THE PLAINS /WCB DROUGHT AREAS • SOUTH CENTRAL CANADA LOOK LATE… POSSIBLY VERY LATE
LOOKING at SUMMER 2013 … cold water in eastern Pacific (-PDO) favors HOT DRY PATETRN for at least SOME portion of PLAINS/ MIDWEST • This assumes there is NO EL NINO eventwhich is still a 25-35% chance • www.WxRisk.com 804 307 8070 • column over at Agweb.com • https://www.facebook.com/WxRisk • email: wxrisk@verixon.net