February and March to May Outlooks 2004

For this forecast I tried to be totally objective in selecting analogue years and preparing the forecast without bias toward the current pattern, or the latest model trends. This is clearly not an El Nino winter nor is it a La Nina, it is instead a neutral season as far as the El Nino Southern Oscillation (ENSO) cycle.

I selected analogue years based on years when “Nino” zone 3.4 was neutral but slightly positive, and also where the zone 4 (westernmost zone) was the warmest. I also avoided the 1950s and 1960s because the measurements are more questionable, and the differences used are anomalies as fine as tenths of degrees.

The best analogues were from January of 1977, 1978, 1979, 1980, 1982, 1993, and 1994. 1978 was immediately dropped because it is such a known cold year that it would tend to taint the whole pack toward colder, and obliterate any message provided by the other analogues. As I plotted the pack of remaining years, it seemed that too much of the US was too cold. So I started trimming out the late 1970s because they were cold. So that left 1980, 1982, 1993, and 1994. The forecast remained very much as presented. I further dropped 1994……still no appreciable impact on the cold forecast, particularly for northern New England and for the Nation’s heartland.

(CONTINUED)

February 2004 Forecast and Mar-May 2004 CONTINUED

Because the forecast is so similar to current model indications for early February,confidence is very high for February (as confidence goes for monthly forecasts). For this forecast to verify, the recent model indications of having the cold shift to the middle of the US (instead of the Northeast) will have to become reality.

While confidence is good for February because the forecast follows (unintentionally) the pattern that is current and expected for the next couple of weeks, the March to May forecast came out exceedingly flat. When I used all of the above mentioned analogue years, the entire country was NORMAL. Eliminating a few of the analogues yielded a picture for March to May with the belows as indicated on the map, but no above normal areas. Confidence at this point is not high for the spring outlook, but indications are for a lot of normal. I even ran a March separately for comparison, and it was similar to the March-May period, showing a shift in pattern from February, and favoring slightly above normal temps in New England and the Lakes!

Mike Pass

DEC 14, 2003 SEA SURFACE TEMPERATURE ANOMALIES

LATEST SST ANOMALIES…….NEUTRAL!!

The Sea Surface Temp Anomalies for the last 12 months

These graphs show the last year of SST anomalies for the 4 El Nino “zones”. Zone 4 at the top, is the furthest west, while 1+2 bottom are closest to South America. Analogue years were picked based on January being slightly positive (or close) in all zones, but NOT strong enough to be an El Nino year. Also, analogues were favored where the warmest was in zone 4.

JANUARY 2004ISSUED 12/16/03 – Mike Pass

MUCH ABOVE = >+4ABOVE = +1 to +4NORMAL = -1 to +1BELOW = -1 to -4MUCH BELOW = <-4 Compared to the 1971-2000 normals

ABOVE

NORMAL

BELOW

MUCHBELOW

BELOW

SO FAR THIS MONTH!!Back to COLD EAST-WARM WEST

MUCH ABOVE = >+4ABOVE = +1 to +4NORMAL = -1 to +1BELOW = -1 to -4MUCH BELOW = <-4 Compared to the 1971-2000 normals

NORMAL

BELOW

MUCHBELOW

NORMAL

FEBRUARY 2004ISSUED 1/20/04 – Mike Pass

MUCHBELOW

MAR-MAY 2004ISSUED 1/20/03 – Mike Pass

MUCH ABOVE = >+4ABOVE = +1 to +4NORMAL = -1 to +1BELOW = -1 to -4MUCH BELOW = <-4 Compared to the 1971-2000 normals

NORMAL

BELOW

NORMAL