WINTER 2014-15 FORECAST REVIEW - PowerPoint PPT Presentation

winter 2014 15 forecast review n.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
WINTER 2014-15 FORECAST REVIEW PowerPoint Presentation
Download Presentation
WINTER 2014-15 FORECAST REVIEW

play fullscreen
1 / 55
WINTER 2014-15 FORECAST REVIEW
192 Views
Download Presentation
gwendolyn-hogan
Download Presentation

WINTER 2014-15 FORECAST REVIEW

- - - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

  1. WINTER 2014-15 FORECAST REVIEW Dogs and cats sleeping together …Mass Hysteria

  2. HYPE… IS GOING TO BE A BIG ISSUE FOR THIS WINTER **It started back in JULY with a few HYPSTER meteorologists issuing forecasts in JULY !! ** Once those forecasts/ hype were issued… Social Media was flooded with “weenies” issuing similar such forecasts. Everyone of these “ forecasts” all features severe cold and huge amount of snow for Midwest/ East coast WEENIE… term used to describe high school students and adults who think they are the next Jim Cantore – (but actually work 3rd shift at WalMart)

  3. THIS is the Twitter Page I post updates on during winter season– and all seasons tyat are about “operational “ (Regular) weather forecasts

  4. BRIEF REVIEW OF LAST WINTER • VAST MAJORITY OF FORECASTS (govt & private) CALLED FOR A MILD or very MILD WINTER • OCT & NOV 2013 WERE NOT COLD AT ALL • MANY INDICATORS WERE UNFAVORABLE FOR COLD/ SNOWY PATTERN IN CENTRAL/ EAST US

  5. BRIEF REVIEW OF LAST WINTER part 2 • SO WHAT HAPPENED? • In NOV 2013 A LARGE POOL OF VERY WARM SSTA (Sea surface temperature Anomalies ) DEVELOPED IN NE PACIFIC / GULF OF ALASKA • THAT POOL OF WARM SSTAs SIGNIFICANTLY ALTERED THE OVERALL PATTERN. • As as long as the Pool of warm SSTAs existed then the pattern would NOT change …

  6. This shows the “ surprise” pool of warm SSTAs that developed in mid NOVEMBER 2013. Most forecasts were already issued by Mid NOV so they missed this

  7. POLAR VORTEX DEVELOPS IN OCT/NOV and LASTS UNTIL JUNE. IT’S SIZE … INTENSITY ….POSITION IS ** CRITICAL ** IN DETERMING THE WINTER PATTERNS OVER ALL OF THE NORTH HEMISPHERE -AO +AO

  8. As you can see the large pool of very warm SSTAs did NOT weaken or move.In fact it increased during the winter

  9. RIDGE PV PV RIDGE ACTUAL JAN 2014 500 MB PATTERN

  10. PV RIDGE RIDGE PV This is what the actual 500 mb pattern looked like in FEB 2014

  11. This shows mean temps of the USA from 12/1/13 to 3/1/14 and impact of the 6 Arctic air mass out breaks 1 3 6 1 4 2 5

  12. This shows AO phases and Intensity from 12/12/13 to 4/1/14. EVERY TIME the AP dropped into “ negative” territory there was an Arctic air mass out break 5 2 6 4 3

  13. WXRISK WINTER 2014-15FORECAST SUMMARY • NOV looks to be a MILD month and 1st half of DEC east of the Mississippi river generally mild • NOT AS COLD AS LAST YEAR… (this is obvious) • NOT as many snow events (many places on East coast had 15-20 ”middle size “ events) BUT bigger winter storms • Increased Risk of ICE STORMS over Ohio valley Middle Atlantic New England

  14. WXRISK FORECAST MAPSDEC 2014

  15. WXRISK FORECAST MAPSJAN 2015

  16. WXRISK FORECAST MAPSFEB 2015

  17. THE DETAILSUNDERSTANDING THE FORECAST • 30 DAY & SEASONAL FORECASTING IS HALF SCIENCE / HALF ART. You have to do it all the time to be good at it. PROBLEMS: • Media plays up USELESS Farmers Almanac. Then e when they bust folks think its a ‘real’ forecast • Issuing Winter forecast in July. 100% CHAOS theory/ rules says its BS. • TV Mets who are pressured by news manager but have no clue what they are doing

  18. SEASONAL FORECASTING is based on: • The CURRENT atmosphere • Current and future Seas Surface temp anomalies/ pattern • Figuring out which factors are going to the DRIVERS or dominating force • SOIL MOISTURE • “WHAT COULD GO WRONG ?”

  19. EL NINO FOR THE WINTER ?

  20. There is some “ skepticism” about a El NINO is REALLY coming this time. Back in March & April it LOOKED like a Moderate El Nino was developing but by JULY the El Nino collapsed

  21. Actual DATA – NOT Models/ forecast - clearly shows el Nino round 2 IS coming and it will be a WEAK El Nino

  22. this easy to read SUMMARY of El NINO Forecasts clearly show a “ WEAK” event for this Winter

  23. All WEAK El Nino temperature anomalies DJF ( DEC- JAN – FEB) since 1900 based on 1951-2010 Based on 1981-2010 climate record climate record

  24. NOT ALL EL NINO EVENTS ARE THE SAME as shown by Recent discovery by Japan’s wx folks

  25. Modoki El Nino events have a HIGH Probability of bringing Colder & Snowier then Normal Winters for central / eastern US

  26. The severely snowy winter of 2009-10 was a MODOKI El Nino- notice how the warm El Nino waters shifted WEST from late OCT to DEC

  27. CURRENT SSTAs in the PACIFIC BASIN

  28. BLOCKING JET STREAM PATTERNS IN WINTER • TYPICALLY WEATHER PATTERNS MOVE FROM WEST TO EAST .. Some times slow sometimes fast • Occasionally a ‘ CONVOLUTED’ Jet stream pattern will form ..in the wx biz these unusual Jet stream patterns are called BLOCKING PATTERN • There are many different types of BLOCKING PATTERNS • They bring about PROLONGED or REPEATING patterns periods of same kind of weather… can last for several weeks

  29. LARGE AREAS OF COLDER THAN NORMAL and WARMER THAN NORMAL OCEAN WATER TEMPS HAVE A CAUSE and /or REINFORCE BLOCKING PATTERNS PDO Pacific Decadal Oscillation -PDO +PDO

  30. -PDO … both SEASONAL AND LONG TERM Tend to Favor the Negative PNA pattern (-PNA) +PDO … both SEASONAL AND LONG TERM Tend to Favor the Positive PNA pattern (+PNA)

  31. CURRENT SSTAs in the PACIFIC BASIN +PDO AUG 2014 PDO = +0.67 SEPT 2014 PDO= +1.08 THERE HAS BEEN SOME RECENT COOLING IN NE PACIFIC

  32. All JAN +PDO = THESE SORT OF TEMPS ANOMALIES All DEC +PDO = THESE SORT OF TEMPS ANOMALIES All FEB +PDO = THESE SORT OF TEMPS ANOMALIES

  33. THE ARCTIC OSCILLATION -AO/ +AO Yes it can get “ cold” in the Winter months over central & eastern CONUS with a Neutral/ Positive AO… but not a sustained cold pattern. It is IMPOSSIBLE to get a Significant and/ or Major East coast Snowstorm without –AO and/ or -AO that moves to Neutral/ Positive AO

  34. The AO during the WINTER OF 2009-10 .. With its non stop big snowstorms-- Historic / severe all winter long

  35. The AO during the Super warm snowless WINTER of 2011-12.. Historic / positive all winter long

  36. SIBERIAN SNOW COVER IN OCTOBER ….and NORTH AMERICAN / US WINTERS 2 WAYS TO MEASURE SNOW IN SIBERIA IN OCTOBER SAI - Snow Advanced Index SCE – snow cover extent

  37. SAI … closely matches AO Taking the SAI into forecast Models DRAMATICALLY improves forecast accuracy

  38. SO WHAT ABOUT OCT 2014? Snow cover expansion in weeks 39…40…31…42… 43 are the KEY As of 10/17 the SCE is at a RECORD setting pace

  39. This shows the snow cover rate of expansion / Advance (SAI)

  40. On left side this shows actual snow cover extent (SCE) while Right Side shows the expansion relative to “ normal” (SAI)

  41. NAO aka “THE GREENLAND BLOCK” IS A CRITICALLY IMPORTANT JET STREAM PATTERN THAT AFFECTS WEATHER PATTERNS OVER Central and Eastern US…. eastern CANADA …Much of EUROPE MODERATE or STRONG –NAO increases chances of Big east coast Winter storms and this Probability goes way up if pattern features -NAO and –AO -NAO +NAO

  42. SUPER MEGA SNOWSTORM WINTER OF 2009-10 FEATURE **RECORD** -NAO VALUES and LASTED ALL WINTER LONG THE RECORD WARM/ SNOWLESS WINTER OF 2011-12… FEATURED NEAR RECORD ** HIGH +NAO ** THAT ALOS LASTED ALL WINTER LONG

  43. This ‘ schematic’ of what Sea surface temperature Anomalies look like in OCTOBER when the NAO was mostly Negative in Winter

  44. ACTUAL SSTAs IN MID OCTOBER RE ALMOST A TEXT BOOK MATCH

  45. SUMMARY FOR WINTER 2014-15 • M.E.I. • WESTERN EL NINO ? (modoki) • +PDO / PNA • -NAO/ ssta in North Atlantic • SIBERIAN SNOW COVER/AO PHASE ??