April 30, 2011

Warm Tomorrow

Today will be a transitional day with low clouds slowly burning off and few residual showers (see satellite pic at 10:15 AM). Want sunny skies for sure? Head just east of the Cascade crest and down into eastern Washington. The air is still cold aloft so we could get some instability and cumulus development, but that will be increasingly suppressed by high pressure building aloft.

Here is the 2 PM Satellite picture.... you see the mottled effect over land...but not clouds over water? A beautiful exam of surface heating causing lots of cumulus!

Here is the upper level (500 mb for tomorrow)--strong ridging over us and ridges are associated with sinking motion, which works against cloud formation.

With strong sun (the intensity today is like mid-August!) and warming temperatures aloft as the winds in the lower atmosphere turn southerly, temperatures will jump on Sunday into the 60s and even some lower 70s west of the Washington and Oregon Cascades. (see forecast for tomorrow afternoon from probcast). Summer will hit the Willamette Valley!

But another trough and an accompanying Pacific front will arrive on Monday...so this warmth won't last.

It is now certain that we will have the coldest April (maximum temperature) on record for Sea Tac (since 1948). And their are a whole collection of other regional cold records that will be broken as well. This month will be Portland's coldest April in 36 years as well as third wettest in history (1940-2011) at the Portland Airport. Astoria, Oregon has still not reached 60 degrees this calendar year, smashing the old record of April 19th 1945. I could go on and on, but I suspect you don't need much convincing.

Many of you have asked what this all portends for this summer's weather. To be honest, I can't tell you--there is simply no relationship that I know of that can provide a useful answer. One thing for sure...there will be plenty of water supply this summer for irrigation and power generation. And this says NOTHING about global warming.


  1. I see. Global temperatures say nothing about global warming. Whatever. Do you belonng to any other churches?

  2. Kevin,
    LOCAL temperatures for a short period say nothing about global warming. Don't understand your comments about churches...cliff mass

  3. He means he thinks that belief in global warming is like a religion, in which true believers' faith will not be shaken by any amount of evidence to the contrary. I'm not saying I think this about you, I'm explaining what he means. Some GW believers are like this--hysterically so--but you tend to be more thoughtful and empirical. Read Bjorn Lomborg.

  4. This talk about churches is really unnecessarily provocative. The truth is that EVERYONE--all sides--would agree that local changes say nothing about global warming.

  5. Lomborg is not a scientist, and his analysis of the science has been heavily criticized by the science community. Given that many of his arguments have been discredited, I would not hold him up as a good resource.

    If you want to learn about climate change, there is no better place to start than the IPCC reports which summarize the literature (though the most recent one is already out of date). If you want to gain a general understanding of the climate system, Global Physical Climatology by Hartmann and Principles of Planetary Climate by Pierrehumbert (more verbose, but very enjoyable) are good reads. If you aren't terribly good at math, you can still probably wade through them.

    Kevin is a troll. However, if he really believes a single station is representative of global temperatures, he should examine an anomaly map: http://data.giss.nasa.gov/work/gistemp/NMAPS/tmp_GHCN_GISS_HR2SST_1200km_Anom03_2011_2011_1951_1980/GHCN_GISS_HR2SST_1200km_Anom03_2011_2011_1951_1980.gif

    Temperature is variable on short time scales on the regional scale - imagine heat being shuffled around the system. For many regions, some years are cooler than the mean, others warmer. What matters is the global temperature, and the average temperature at those stations, and that is rising: http://data.giss.nasa.gov/gistemp/graphs/Fig.A2.gif

  6. It looks like April will end up with a temperature average of 45.5,which will be the second coldest on record at Sea-Tac. April 1955 is still the coldest, at 44.6.Although, one can argue that this April was colder because temperatures at Sea-Tac have warmed dramatically since the airport expansions and urbanization that has been occurring since the 1960`s.

  7. Climo man,
    I am talking about maximum temperature..what I think most people care about I suspect. And for that, this April is the record coldest. If you look at average daily temperature, you may be right. I should note that minimum temperature is far more susceptible to urbanization issues than max temps....cliff

  8. Cliff,
    On that subject I would love to know more. I am amazed at how much warmer the low temps cab be in the city and have often wondered specifically what gives off the heat and if our large urban areas will continue to warm as they expand. I also note that Seattle and Portland are at lower elevations than surroundings and how much does that make the heat island effect look bigger than it is.

  9. cliff, i really appreciate your site/blog and enjoy all your accompanying graphs and satellite photos. i can't understand why people have to become snarky and uptight over this stuff. it is what it is....

  10. yeah, I'm kinda curious about summer weather forecasting. What provides hotter or wetter than normal summers around here etc.

    maybe sometime down the road.

    this I do know, I've noticed the extended outlooks have changed. They have May still wet and cool. Cool through July. Took away some heat and dryness later on too. Whats up.

  11. To say that the cold temperatures say nothing about global warming is a bit of an oversimplification, but just barely. It would be more nuanced to say that the record cold is related to global weather patterns, and thus global climate change may or may not be playing a role. We just don't understand the complexity on a planetary scale yet.

  12. Very slight frost here in Kingston this morning. Latest I have observed in the last 21 years is May 15 but most last frosts usually happen in March or April. Today will be a good day for the hawks, eagles and swallows.

    Global climate change is fact, something that has been measured and its effects observed. Like gravity, its not something that one believes in. Global Climate Change is here, whether or not one believes in it.

  13. I think it's not possible to say that increasing frequency of significant weather (stuff that makes us talk about how wacky the weather is) is definitely unrelated to climate change.

    Our weather this year has been impacted by a cold water event off Peru. Planetary waves that describe that activity have climatologic-scale drivers, no? Like how stratified is the upper ocean, e.g. So does our weather say SOMETHING about climate change?


  14. Well, we got up to 55 degrees late this afternoon on Sinclair Island. It was still 53 at 2pm. We had a little onshore flow this morning with some low clouds drifting by and a brisk south wind. It boggles the mind how a mostly sunny day in May and a ridge of high pressure only gives us 55 degrees. Other than that it was a beautiful day that brought out a few butterflies. Saw my first Blue Azure of the season, about a month late. Also, the swallows arrived today.

  15. Kudos Ferdi. That was my thought too. Absolutely no complaints, lovely day! But I was thinking, high pressure, 100 percent pure sunshine, no breeze, and it feels no warmer than 55 degrees. A pitiful beautiful day, lol.

  16. NWS is predicting colder than usual May, June, July. I know you haven't wanted to predict just yet, but any thoughts?

  17. Ignore Kevin's comment, the climate has and always will change. Just as mountains rise and fall and continents drift the earth is in constant change. Now the argument would be, are humans affecting the climate? If you look at the down sides of a warming or cooling climate, in my opinion a cooling climate would be devastating to modern civilization.

    Take a good look at humane history. Historically when climates cooled disease and famine would devastate. On the flip side when climates would warm civilizations would prosper.

    Don't take my word on it. Grab a good unbias book on the subject and form your own opinion.

  18. Irrigation, power generation, and salmon. Don't forget about the last of of those!

  19. I completely agree with Shasta's statement, and would just add that the answer regarding human impact is most likely unknowable. There are simply too many variables to consider.

    I suppose I may be a troll. I just I recently discovered this site, and am thrilled with it, as I will be moving to Seattle soon. I wish we had a blog like this where I live now!


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