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.
Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.
SPRING 2013 and SUMMER 2013
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
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
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
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.
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
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
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
HOW and WHY DOES ANALOG SEASONAL FORECASTING WORK?
GOING into SPRING OF 2013… the current MODERATE -PDO Values are EXPECTED to continue.
ModeratelyNEGATIVE PDO Rainfall MAM
ModeratelyNEGATIVE PDO for TEMPS for MAM
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 ***
Above & Much AboveTemps
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
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
APRIL 2013 TEMPS ** FORECAST ** BASED ON CFS IN EARLY MARCH
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