Oregon-AMS Meeting Summary for October 17, 2009 - Program

In Memoriam Memory of past members and founding fathers.

17th Annual “What Will the Winter Be Like?” Meeting

President Bobby Corser's opening presentation

This very popular meeting attracted 275 people this year – a new record.  We were hosted by our good friends at the Oregon Museum of Science and Industry (OMSI).  Local meteorologists gave their best forecast for the winter of 2009-2010: Tyree Wilde, Warning Coordination Meteorologist, National Weather Service, in Portland; George Taylor, Applied Climate Services (retired Oregon State University Climatologist), in Corvallis; Pete Parsons, Oregon Dept. of Agriculture Meteorologist in Salem; and Kyle Dittmer, Hydrologist-Meteorologist, Columbia River Inter-Tribal Fish Commission, in Portland.  Many TV and radio media were present, too. 

Rainy weather and thunderstorms were going on during the meeting.  We checked the real-time radar images in-between each speaker to see the action outside.

We offered the “Snowflake Contest” for a third year in a row.  Folks had the chance to guess the date and time of the first official recorded snowfall, based on Portland NWS data.  The four winners will receive eight general admission passes donated by OMSI.  Response was great.

Jim Todd's presentation
Jim Todd of OMSI gave the Welcoming remarks. 

Mark Nelsen's presentation
KPTV-Fox 12 Chief-Meteorologist Mark Nelsen, OR-AMS Councilor, reviewed the 2008-2009 winter weather.  The great Snow of December 2008 was a dominant theme. 

Steve Pierce's presentation
Steve Pierce, OR-AMS Councilor, gave a review of Portland snowfall potential based on 1871-2009 data. 

Bobby Corser, Oregon-AMS President, then introduced each of the guest speakers.   

Tyree Wilde's presentation
Tyree showed how El Nino has been developing in the tropical Pacific in recent months, with persisting +0.5 to 1.5 deg C sea-surface temperatures (SSTs).  The NOAA/NWS probabilistic forecast calls for El Nino to strengthen and elevated chances for a warmer and slightly drier than normal winter.  Tyree did note that significant storms can occur during an El Nino winter and that we should not be caught off-guard.

George Taylor's presentation
George said that whatever El Nino we had has now peaked and is dying out, as noted in the Australian Bureau of Meteorology’s current SOI index and NOAA’s Multivariable ENSO Index.  He gave the most credence to the NOAA – Climate Diagnostics Center product of forecasted SSTs, which shows a decay of warm water back to near normal.  George thinks we’ll have an active early season with a mid-winter slow down.  Expect below average precipitation, above average temperatures, average mountain snow, and low valley snow.

Pete Parson's presentation
Pete says this is a “atypical El Nino” with higher-than-average likelihood of above average valley rain and mountain snow, Cascades and westward, and drier east of the Cascades, for January, with increased flood risk west of the Cascades.  He sees no clear climate signal in the top three analog years for November and December, so anything is possible (i.e., highly variable).  Expect average chance for valley snow.  Pete’s forecast uses analog- or surrogate-years, past years that indicate a repeat of specific weather patterns based on SOI and ONI indices across the Pacific Ocean.

Kyle Dittmer's Presentation
Kyle opened with a question to ponder: “I know what the computer model says, but what’s really going to happen?”  His analog-year forecast approach uses solar forcing, SST, and hydro-climate (past water years).  The sunspot counts have been very low and portends to weather similar to winter 2008-2009.  He believes that El Nino will not happen and that we are trending to ENSO-Neutral.  Kyle calls for near normal temperatures, but on the coolish side, with the coldest departures in December and February.  Precipitation will be near normal, but a little high in November and January.  The crowd gasped when Kyle said, “Expect six snow events in Portland, during December through February, 2-3 inches each.”

Lastly, President Bobby Corser extended an invitation to the crowd to come join us for lunch in the OMSI Café and talk with the forecasters.  Afterwards, we were given a special demonstration of OMSI’s new “Science on a Sphere” project, partly funded by NOAA and NASA.

In an effort to help bring weather science to the local community, our chapter has partnered with OMSI since 1999 to host the popular Winter Weather meeting.  OMSI and the Oregon chapter benefit from the attention generated by ample local media coverage. 

Notes by Kyle Dittmer.