Pacific Northwest Weather

[andycottle]

Looking at the latest GFS this morning....our very showery and unsetteled weather continues through at least the upcoming friday period as systems will be coming in about every 48hrs or so. The next system in a line up of storms to watch is wednesdays syetem. Could be a fairly wet and especaily WINDY system as a 996MB low skirts right up against the upper north Washington coast. For us here in the Puget Sound region...probably just some breezy winds of 25 to 30mph. In fact, for wednesday morning....850MB winds are at 30kts out of the SSW, and 500MB winds at 40kts from the SW. So it is something to watch!

Temps should remain seasonably mild and in the upper 50`s to near 60 per MRF MOS. From about next weekend onward...looks like a ridge of high pressure gives us some nicer weather. -- Andy

[AnthonyC]

Very heavy rainfall this morning!! A rainband moved through the central Puget Sound...my guess is it was created by convective heating...the convective temperatures is 59F today...currently I'm sitting at 59F. If you look at the radar loop, the band became very organized and intensified rapidly.

As for the rest of the day, a PSCZ may form...right now winds aloft are from the southwest but are forecasted to switch to the west. Nothing too intense, but I would not be surprised if someone saw a flash of lightning or heard a clap of thunder.

This upcoming week looks unsettled...a showery regime...but temperatures should at least remain near normal, if not slightly above. Like Andy stated, Tuesday night is still something to watch as a deep surface low tracks off our coast...I'll keep you updated.

Anthony

[snow_wizzard]

Another half inch to add to the increasingly soggy total for this spring. This was certainly a case where a lot of rain fell in a very short time. We had about a quarter inch in one hour at my place. I am going to be absolutely sick of mowing by the time this spring is over! The lawn (over a quarter acres worth) is growing at twice its normal rate due to all of the rain. I will say I am 100% sure the drought is over. The only thing that could remain a problem is the low snowpack. On the other hand, if this regime continues we will sail through the summer with no problem at all. It certainly looks as if the next front will put us well above normal for the entire month of May.

TT...I agree, for now, that 1968 may not be a match, but I am going to continue to watch it. If we follow it for a few more months I will begin to think otherwise. I have really studied that year and this pattern is very, very similar to what dominated the first half of it.

[snow_wizzard]

I must admit, I am a bit disappointed that the below normal temperature part of this pattern is looking like it will only last a few days. The models show the really cool air will come in tomorrow or tomorrow night. It appears the best shot at solidly below normal temps may be on Friday as a pool of cold air ahead of a building ridge moves through the area. All I can say is that we have had prolonged warm periods in the past and they invariably end. In general when it changes it is very sudden and with little warning. 1992 is a fabulous example. The first half of the year was very warm and second half cold. The same was true in 1983 and many other years. I may have to revert to my original prediction of this year being warm the first half and cold the second half. Some signs the past couple of months had caused to me to change my assesment of that, but it is becoming increasingly clear that the cold spring that appeared to be in the cards has fallen through. TT and I both got fooled on that one!

[snow_wizzard]

By the way...I have some interesting proof that the current weather patterns are more aligned with the 1950s through the early 1970s, than what we have recently observed. I wrote down all of the analogs for one week from both the GFS ensemble and the Canadian ensemble, and the asverage analog year from both was 1968. In other words I added up the years and divided by the number of analogs, which was 5 per day per model. The chances of the average year being so far back are quite low when you consider the analogs only go back to 1950. That means the average year was only 18 years after 1950, but 37 before now. Since I did that the analogs continue to be consistently from before 1975. The 0z run of the GFS today had 1951, 1954, 1955, 1973, and 1983 as analogs. Every one of the winters following those years had very cold weather. 1973 did not have a full fledged Arctic blast like the others, but areas north and east of Seattle had 10 consecutive highs of 32 or below in Janaury 1974.

The big mystery to me is why we are still seeing so much warm weather if we are matching up with such cold years. One possible reason is that we seem to be getting patterns that occured during the above normal temperature periods of those years. Why is that? Why are we seeing warm patterns with the same upper air patterns that we saw in the 50s and not like the warm patterns in more recent years. Could this mean that patterns matching the cold periods of those years are close at hand? We can only hope so! It is interesting to note that the cold period in April was the most like a cold period in April 1953, at least at the upper levels. In short, it is amazing how many analogs we are seeing to the 1950s.

[TT-SEA]

Hate to say it... but you are ignoring global warming.

Completely ignoring it.

You cannot do that and be accurate.

One of the reasons that it is warmer with the same upper air pattern that bought cold air in the 1950's... it that the Earth is warmer.

You can debate the cause... but it is very real.

You need to factor global warming into the equation. The old rules no longer apply.

And we are still in positive PDO territory anyways. It takes 2-3 years for the weather patterns to adjust after a regime change. And it still has not happened.

We will not have a winter like those in the 1950's anytime soon.l

[snow_wizzard]

We shall see on that! I have a big time feeling that something big is going to happen very soon. I am still betting that we will see a major cold period before this year is over. It will not be long before we know if I'm right!

[TT-SEA]

Here in North Bend... we always seem to catch up to other locations when it comes to rainfall.

Even when it seems everyone else is ahead and we missed most of the action.

This morning some places had received .50 and we were sitting at .12 for the day.

Now we are at .90 and its still raining hard here. We will easily go over one inch for the day.

[snow_wizzard]

That is very true TT. North Bend always does seem to pull a rabbit out of the hat. If it were not for one VERY HEAVY and very lucky shower today you would be way ahead of me. As it is we are sitting at .80 for the day. We had a shower that dropped .20 in 5 minutes a couple of hours ago. I mean it POURED!

[andycottle]

Had a good deals worth of rain early this morning that statred around 9a.m or so. And this heavy rain that came through my area was due to a moderate band of showers that developed quickly just SW of Seattle sometime after 8a.m this morning. Think this band that was in my area lasted maybe close to half hour so. Then rest of the day was just cloudy with a few spotty showers/light sprinkles. Though temp remained mild. So from the rain we overnight last night and into today....I`ve recieved .35" of precip.

My high today was 61 with a low of 57. Geee.....what`s that tell ya?! lol. That a strong SW flow and mild airmass is definally in place!

-- Andy

[snow_wizzard]

The rainfall total for Covington so far this spring stands at 10.77 inches! That is 51% above normal, and looks like the mother lode of rain is coming later in the week.

I am ready to jump on the warm weather bandwagon for early next week. It may begin as early as Saturday or Sunday. Right now it looks like we could hit 80 on one or two days, but it appears at least the sunny portion of the warm weather will be short lived. It would not surprise me if the high does not set up as well as the GFS is showing, but we should be able to squeeze at least one or two clear days out of it. I must admit a clear day would be nice. It has been so cloudy and muggy this month! I am also predicting some fairly respectable low temps late this week as we are in transition from this trough to the ridge. Some areas will likely dip into the 30s. That is assuming it actually does manage to get clear for a change...

[R-Dub]

5/15/05 LK Goodwin WA
7:48:10 PM CURRENT MIN/MAX
Temperature (ºF) 55.8 55.8 / 63.8
Mostly Cloudy
Humidity (%) 92.9
Wind (mph) N 0.0
Daily Rain (") 0.27
Pressure ("Hg) 29.77
Monthly Rain:0.87 "
Dew Point:53.8 ºF

Even with the showery day, I still managed to walk the dogs, and take them for a boat ride and stay dry. All in all not a bad day!

[snow_wizzard]

R-Dub...It would seem that you have frequently been in the rain shadow this year. Is that normal for your area? It is amazing that you have only had .87 so far this month. I am already well over 2 inches!

[andycottle]

Snow wizzard,

So far this month I`m at 1.34", and for the year so far I am at 11.60".
-- Andy

[R-Dub]

We are frequently in the rain shadow, but it seems for the last 2 months its been a little more then usual.

[andycottle]

Good evening folks.

Latest GFS this evening still showing a very showery and unsetteled weather pattern for the monday through friday period. So with that said, the next in a series of storm systems to watch this week will be a weak trough of low pressure for tomorrow, with the main and of most concerned system...comes wednesday morning.

The one for tomorrow will probably be similar like the one we had today. Moderate to heavy showers in the morning, then cloudy with scattered showers in the afternoon. However, the real eye watching system will be around the wednesday morning time frame as a 996MB low weakens to 1000MB as it moves right up the Washington coast. And during this time, upper level winds pretty gusty as 850MB winds are from the SW at near 40kts with 500MB winds out of the south at 50 to 60kts. Also, this system will riding on a nearly 120+kt jet. So this sytem should be pretty windy for the coastal sections of Washington.

As for as temps go...looks like they`ll remain seasonably mild through this week. However, from about next sunday onward....we could be looking at some much nice weather along with some VERY warm temps.

-- Andy

[TT-SEA]

Somebody was betting on unseasonably cold air this week with temperatures way below normal.

[andycottle]

Interesting AFD this evening! Hey Tim...sounds like an exciting afternoon! And hey...maybe a PSCZ too. We`ll see though.

DISCUSSION...SHOWER ACTIVITY HAS BECOME MUCH MORE SCATTERED THIS EVENING SINCE THE SUN HAS DROPPED...HOWEVER NEXT SURFACE TROF STILL LURKS OFFSHORE. THIS FEATURE IS EXPECTED TO MOVE ACROSS THE AREA LATER TONIGHT FOR ANOTHER ROUND OF SHOWER ACTIVITY.

ONCE THIS PASSES THROUGH...WILL LEFT WITH A COOL UPPER TROF WHICH WILL CROSS WESTERN WASHINGTON LATE MONDAY...WHICH HAPPENS TO BE EXCELLENT AS FAR AS TIMING GOES. WOULD EXPECT A BIT OF SUNSHINE DURING THE DAY WHICH COMBINED WITH THE COOL AIR MASS OVERHEAD SHOULD DESTABILIZE THE ATMOSPHERE NICELY. ETA40 CATCHES ON TO THIS IDEA BY GENERATING CAPES NEARING 500 J/KG...AND THIS IS WITH A TEMP OF ONLY 55 DEG. THE UPPER TROF SHOULD ACT AS A GOOD KICKER SO CONVECTION SHOULD BE FAIRLY VIGOROUS. WOULD EXPECT SOME THUNDERSTORMS AND WITH THE FREEZING LEVEL NEAR 5500 FEET...POSSIBLY SOME SMALL HAIL IN THE STRONGEST SHOWERS. MAY DO AN UPDATE SHORTLY TO ADD THIS MENTION TO THE FORECAST FOR MONDAY. NO CHANGES PLANNED BEYOND THAT. CERNIGLIA

[snow_wizzard]

Wow! Yet another band showers showing up on the radar about to hit my area! I cannot believe what a wet spring this has turned into. That is certainly an exciting forecast discussion for tomorrow. We may indeed see some excitement, and possibly more heavy rainfall totals.

TT...I admit this looks like more of a wet period than a cool one. In general periods that are this abnormally wet are not all that cool.

Speaking of abnormally wet...Ellensburg had another quarter inch of rain today. That may not sound like much until you consider their normal for the entire month of May is 1/2 inch. That combined with the inch and one half they had the other day, means they are at no less than 4 times their normal for the entire month! The GFS is showing that the eastern thrid of the state could also have a monster rain later in the week. Every part of the state is getting their turn at heavy rain. What a comeback!

Yet another nice match for 1968! The north central part of the country is having a very cold May, while we have been warm and wet. 1968 had exactly the same combination! I agree with TT that there are some differences (before March), but we all of the sudden seem to be perfectly mirroring 1968.

[andycottle]

Latest GFS this morning shows that after we get through this very showery and unsetteled weather pattern which lasts through this upcoming Saturday.... a large ridge of high pressure looks to builds back into our region. This high pressure dome starts to build late saturday into sunday and lasts all the way into about the 28th. And the ridge looks to have 850MB temps of +9 to near +12C and 500MB heights of 576DM to near 580DM. So if this holds out, we could be looking at the some rather nice weather and very WARM temps of say....high 70`s to possibly lower 80`s at the warmest.

-- Andy