Updraft: September 1, 2009 Archive

Winter Forecast: Mild or wild?

Posted at 8:21 AM on September 1, 2009 by Paul Huttner

Tropical Pacific sea surface temperatures show warming water as El Nino strengthens.

Welcome to September.

It may seem a bit early for winter predictions just yet, but the Farmer's Almanac is going out on a big limb this winter. The forecast calls for a bitterly cold winter in the Nation's midsection between the Rockies and Appalachian Mountains.

This is at odds with the official forecast from NOAA's CPC. A strengthening El Nino in the Pacific Ocean is leading NOAA to forecast higher chances for a milder than average winter in the Upper Midwest.

There is statistical evidence that NOAA may be on the right track here. In the 17 El Nino events since 1958, the Upper Midwest has experienced a mild winter about 70% of the time. During these years temperatures often average out 1 to 2.5 degrees above average in Minnesota.

The Farmer's Almanac offers some anecdotal claims of accuracy, but does not give any statistical accuracy numbers.

My money is on NOAA this winter. It is pretty tough to have a colder than average winter in Minnesota during an El Nino year. There will likely still be cold snaps, wicked arctic outbreaks and sub zero wind chill babble this winter. There may also be extended mild spells above freezing, and it may be tougher to hold a consistent snow cover this winter.

Could we see bare ground in January?

Stay tuned.

PH

SoCal Fires: Smoke plumes visible on doppler radar

Posted at 3:05 PM on September 1, 2009 by Paul Huttner

Los Angeles doppler radar loop shows smoke plumes from fires billowing north of La Canada and the 210 freeway toward Palmdale.

You don't see this everyday.

Smoke plumes from the fires north of LA are clearly visible on doppler radar in Los Angeles today. The radar beam reflects back off of smoke particles and appears similar to rain showers.

The Station Fire is only 5% contained as of this afternoon. It is burning an area now well over 100,000 acres.

There is one very interesting meteorological aspect to this fire. It is not a Santa Ana Wind driven event. In fact winds have been relatively light in the Los Angeles area the past few days. This is fortunate, because Santa Ana Winds generally blow from the northeast at speed of up to 60 mph. If the Santa Ana's kick in, we could see a firestorm driven down into heavily populated areas southwest of the fire, which has remained largely in sparsely populated steep mountains and canyons so far.

The good news is so far the Santa Ana winds are not in the forecast. Meteorological conditions do not favor a Santa Ana event the next few days. There is some chance that higher pressure building over the inner mountain west could turn winds into the northeast by this weekend. That could threaten new areas north of Los Angeles.

Let's hope they can get the fires contained by next week. It's really early in fire season, and the Santa Ana's will blow sooner or later.

PH