There was quite a bit of discussion at the Winter Weather Meeting (2 weeks ago) about how this El Nino in the Central Pacific wasn’t quite a “normal” El Nino. I think it was George Taylor that pointed out the subsurface water wasn’t as cold as it should be during this type of event. Several speakers even thought El Nino might just go away during the Fall, leaving us with a “La Nada” winter. So I’ve been keeping an eye on the weekly updates on ENSO evolution here. There has been a bit of a change in the last 2-3 weeks (the last data those speakers had was from the first week or so of October. Here’s an image: You definitely need to click on it to get a better view. Several things stick out. First, notice that the SST anomalies came up during the summer (El Nino is developing!), then things really flattened out for awhile (or even cooled quickly in Nino1+2) in the last summer and early Fall. Now the warming has resumed. It’s noticeable in all parts of the equatorial Pacific. The 2nd thing to notice is in the Nino 1+2 part of the Pacific. That’s the area closest to South America. I remember that lots of us at the meeting noticed the cool spot developing near the coastline. Was this the beginning of the end of El Nino? Maybe it is going to just fade away? At least those were my thoughts. Well, now that’s gone or going away quickly. It’s looking like El Nino has been strengthening, not weakening in the last few weeks. This is the latest statement from CPC: Based on current observations and dynamical model forecasts, El Niño is expected to strengthen and last through Northern Hemisphere winter 2009-10.
Now discuss amongst yourselves…I’ll post about our upcoming active weather pattern later.
10 PM Update:
Looks like some fun the next 7 days…November is here for sure. First we have a nice “gap” wind event coming up tomorrow and most of Wednesday. Of course that gap would be the Columbia River Gorge. 00z WRF-GFS shows maybe 7-8 millibars easterly gradient. We tend to get strong east wind events when the atmosphere overhead is quite warm (a strong inversion). That will be the setup tomorrow and Wednesday. 850mb temps get up to around +15 C by Wednesday morning. Too bad it’s not late August…we’d hit 85 or so. Instead we’ll be lucky to hit 60 degrees due to cooler air coming in through the Gorge.
A massive storm develops in the Gulf of Alaska by Thursday, bottoming out near or below 950mb. The cold front with that system races through the Pacific Northwest Thursday with strong southerly wind (gusts to 70 at the beaches and maybe 40 here in town?). Plenty of rain too…oops, I still have 3 leaks in my roof. I just told the contractor this morning that it would be dry Thursday…double screwup there shooting from the hip with the forecast. A strong westerly jet Friday through Sunday means numerous disturbances with plenty of rain/mtn. snow. If you get a chance check out the Wave Watch model too. It shows 30 ft. swell arriving at the coast from the big storm by Friday.
Chief Meteorologist Mark Nelsen