Friday, March 20, 2009

The "Weak" Front


OK...that turned out not to be such a weak front. There was no indication in the models we would have such a sharp transition and with no coastal radar we could not see it coming. A convective line formed on the front with very heavy precipitation...take a look at the radar..you can see the reddish color of very intense precipitation. The observations at the top of the UW Atmos. Sci building shows the dramatic nature of the transition...substantial wind shift, sharp pressure trough, sudden drop of temperature and increase of humidity, and increase in winds to 30 mph (see figure). Or look at the Seattle profiler (image)...a very sharp shift from southerly to SW winds and big temp decline. Finally, you can see the line in the visible satellite imagery if you look carefully (image).

15 comments:

andycottle said...

With frontal precip not being able to be seen coming in from the coast, this is yet another reason why coastal radar is so badly needed.

I to saved the same radar image from earlier today. That was a pretty rainy, rain squall that came through and very intense.

Lauren said...

More than just the rain squall that wind was pretty fierce when I was biking home right after the squall.

Weather Is My Life said...

If we had been able to see that front coming in yesterday, how much more unexciting it would have been when it came through here! It was definitely an exciting short time to be outside in it!

RobbyRob said...

I agree that it is a little more exciting not knowing it is coming. I do however know that at least one person has died due to the sudden burst of wind (and possibly saturated soil, not sure if the trees snapped or were uprooted). Coastal radar would have picked this up and they could have at least spread the word on the radio/news to take shelter in a safe place.

Josh-B said...

Noaa then is responsible for the death?

evilzenscientist said...

That explains the crazy rain in Issaquah yesterday afternoon.

andycottle said...

Yesterdays rain squall was to me, very much like what you see in the mid-west. It comes down hard and fast, then it`s done with! Except there was`nt any thunder or lightning that I was aware of.

Did anybody else have lighting/thunder with yesterdays rain squall?

Weather Is My Life said...

RobbyRob, or at least to do whatever each person wanted to do - in my case maybe I wouldn't have minded so I could go be outside when it came...

Harrison said...

Anyone remember that rain squall that came through and flooded out that lady's basement and killed her about three years ago? It simply amazes me that with our growing population, congested roadways, and ever expanding urban areas that we do not have a coastal radar. At the very least it might save one life a year, and in my estimation, there's no price tag put on that.

Seeingred said...

I am so sick of "weather fans" who think it is "exciting" to not know when intense weather is going to hit. I wonder why you aren't the "danger boy" of the news stations--you know, the guy that is always out getting pelted by the waves at Alki during storms. It would be so fun!

andycottle said...

Well that is sometimes the 'supprize of not knowing'. Can be more exciting, but can also can cause injury/ destruction and so forth. So guess there are two sides to this dilemma when it comes to storms.

Keeping one's head above water said...

when we stopped in longview from portland, the wind was fierce! Plus there were definate t-showers around because I saw their flat bottoms.. I live in pullman long enough to know what they look like and how is rained!!!

Tony said...

Radar article in Seattle Times:

http://seattletimes.nwsource.com/html/localnews/2008902423_weather22m.html

Henry said...
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Henry said...

Andycottle, yes there were reports of lightning and thunder, but that's in the Fraser Valley up here in Canada. Has anybody seen any news articles on this event? I would like some for my work..thanks!