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Thursday, July 30, 2009

Seattle hits 103 -- Welcome to the hottest day ever!

Seattle hits 103 -- Welcome to the hottest day ever!

Seattle hits 103 -- Welcome to the hottest day ever!

Wearing a bag of ice water on his head, baseball fan Kirk Schlemlein, of Snohomish, Wash., reacts as a friend sprays water in his ear while trying to keep cool during a baseball game between the Seattle Mariners and the Toronto Blue Jays, Wednesday, July 29, 2009, at Safeco Field in Seattle.

Story Published: Jul 29, 2009 at 5:00 PM PDT

by Scott Sistek

SEATTLE -- It's a day for the weather history books. For on July 29, 2009, Sea-Tac Airport hit 103 (39.44 °C) degrees just after 3:30 p.m. for the hottest day on record in Seattle, with records stretching back to 1891.

The previous records were 100 (37.78 °C) degrees set July 20, 1994, July 16, 1941, and June 9, 1955*.

Here are the preliminary high temperatures at 5 p.m. (Link to a good Fahrenheit to Celsius converter:

  • Vancouver, WA: 107 (41.67 °C)
  • Kelso: 106 (41.11 °C)
  • Portland: 106 (all-time record: 107)
  • Chehalis: 106
  • Renton: 105 (40.56 °C)
  • Tacoma: 104 (40 °C)
  • Olympia: 104 (ties all-time record)
  • Shelton: 104
  • Seattle (Sea-Tac): 103 (all-time record)
  • Seattle (Boeing Fld): 103
  • Gig Harbor: 103
  • Arlington: 102 (38.89 °C)
  • Bremerton: 102
  • North Bend: 102
  • Everett: 100
  • Friday Harbor: 97
  • Bellingham: 96
  • Port Angeles: 92
  • Forks: 83
  • Hoquiam: 77
It's the second all-time weather record set on Wednesday in Seattle. The lowest temperature recorded so far today was 71 degrees, and it's a safe bet we won't drop below that before midnight tonight. That means we have shattered the record for warmest low temperature which was set... Tuesday. (Well, tied last night at 69. The low was also 69 on Sept. 2, 1974). Put another way, this is the first day ever that the temperature failed to drop below 70 degrees at some point during the day. Miami would be so proud...

Too hot to play outside today!

(Incidentally, if you're wondering about the asterisk by the June 9, 1955 note above, technically speaking, that 100 doesn't count as an official 100 degree high. Why? Just like the 1941 reading, that was taken at the Downtown Federal Building. But in 1945, the official reporting station for Seattle was moved from the Federal Building to Sea-Tac Airport. So the 1955 Federal Building reading doesn't count as an official record.

It's sort of like pitching a no-hitter for 9 innings, then giving up a home run in the 10th. You accomplished the feat by usual standards, but the record books don't recognize it.)

Other all time records are poised to fall as well. Bellingham hit 95 after 1 p.m. breaking their all-time record high of 94 degrees. Others in jeopardy: Olympia's is 104 (they hit 101 Tuesday) and Portland's is 107 (they hit 106 on Tuesday)

Hot Weather News:

The heat is causing a myriad of problems across the Puget Sound area, aside from people scrambling to keep cool.

  • Snohomish PUD says three substations went out near Monroe, knocking out power to about 14,000 people in the Monroe area.

    Officials say the heat caused transmission lines to sag into trees, causing brush fires. It also knocked out three substations.

    They were able to get all but 2,500 back online by 2:15, and then everyone else a short time later, but as power was coming back on, several transformers were reported on fire and torching the power poles, keeping firefighters busy across the city.

    Power outages were an issue in other parts of Western Washington as well. Some 10,000 people in Tacoma were without power for several hours during the record-breaking day, as were 700 others on Vashon Island. In Renton 2,800 residents were also left in the heat for an hour.

    Some 3,300 customers of Seattle City Light spent a few hours in the dark and without the relief of their fans on Wednesday night. And 300 Bellingham residents were forced to turn in for the night without power as crews were repairing an underground cable.

  • A flicked cigarette butt sparked a brush fire in the median of I-5 near Tukwila, the state patrol says.

    Flames were seen shooting up from the trees between the north and southbound lanes near S. 200 Street. The fire was put out a short time later, with the help of a foaming truck from Sea-Tac Airport, but traffic was backed up as far as eight miles through the afternoon as firefighting vehicles were blocking lanes to fight the fire.

  • Firefighters were also busy in West Seattle and Auburn battling house fires. The West Seattle one broke out around 1 p.m. in the 5200 block of 45th Ave. SW. People were inside when the fire started, but all got out safely. Two firefighters reportedly required treatment for heat exhaustion.

    About an hour later, a fire broke out in a home in the 600 block of 24th Street SE in Auburn. A neighbor called 911 after seeing smoke and flames coming from the back of the home.

    Firefighters rescued two dogs from the home, but one didn't survive. No word yet what caused that fire.

    Later in the evening, brush fires kept firefighter busy. A brush fire near the University of Washington's horticulture center scorched several acres. Firefighters had to stretch their hoses to the length of four football fields just to reach the flames.

    And at Lake Ballenger in Snohomish, flames shot more than 10 feet into the air, and a helicopter was called in to douse them.

    Want to buy an air conditioner or fan? Good luck!

    Now that the region has suffered through the warmest night on record, thousands went in search of air conditioning and fans.

    Lines were very long at several hardware and department stores -- including this line at the SoDo Sears store.

    Why over 100 today?

    We have the perfect heat scenario of an incredibly strong ridge of high pressure. That alone has been baking the Northwest into the 90s of late.

    But Wednesday, we finally have the icing on the cake to make this the "perfect storm" of a heat wave -- the hot, east wind.

    It took a while, but a thermal trough has finally developed that is drawing in the hot, dry east wind. Put the two together, and it's like mixing fire and oxygen.

    Locally, the east wind makes it hotter for a few reasons. One, that air is coming from Eastern Washington, where is hot to begin with. Second, as that air crosses over the Cascades and then sinks down, it warms further. For those living along the foothills, this is akin to living at the end of a blow dryer and why your highs are among the hottest.

    Now, as to why it's sticking around so long, the weather pattern over North America has two big features -- a big, big ridge of high pressure anchored along the western third (stretching from Baja to almost the Arctic Circle) and a big, big area of low pressure anchored over Hudson Bay.

    Not only has that ridge baked the West Coast, but on the other end of the scale, that low has made life miserable for the rest of the nation east of Denver. There, summer has gone into hiding, with relentless rain and thunderstorms. New York City is on pace for one of their coldest July's ever.

    With such exaggerated patterns, it's hard for them to budge because they are so strong they get stubborn. Incoming weather systems, typically weaker around here in summer anyway, are no match to move a ridge of this size, and then in turn, this ridge doesn't move to push the eastern low out of the way. It's like having a disabled semi jackknifed on the 520 bridge -- there's just not much room to move.

    That ridge, in turn, keeps the thermal trough over our area. Heat waves usually don't go longer than two or three days because the ridge gets nudged east by the westerly flow of the planet, and once the thermal trough moves east of the Cascades, it opens the door for the cool west wind to kick up. But with the ridge so strong, it's able to hold back the ocean breezes and maintain the thermal trough right over Western Washington.

    The last time we saw this pattern was 1977 and 1981, our two current heat wave champs. 1981 is notable for 5 days in a row over 90, including a 99 and 98, while 1977 had an 18 day period where it was over 79 every day (15 in a row over 80), 13 days over 85 (9 consecutive) and six days over 90 (4 consecutive).

    The east wind should also at least eat away at some of this lingering humidity, but it'll still be a bit muggier than a normal heat wave - not that anything else is much normal about this heat anyway.

    Record Check:

    A quick list of other records that might fall this week:

    • Consecutive days at or over 90: 5 (Aug. 7-11, 1981). Current forecast: 4, Potential: 6
    • Consecutive days at or over 85: 9 (Aug. 5-13, 1977). Current forecast: 9. Potential: 11
    • Consecutive days at or over 80: 15 (July 30-Aug 13, 1977) -- Current forecast: 11, which stretches through the end of the extended forecast. Potential: ??? (Incidentally in the '77 streak, the 14th was 79, there were three more 80s afterward.
    • Number of 90 degree days in a month: 7 (July 1958)
    • . Current forecast: 6. Potential: 7
    • Number of 90 degree days in a year: 9 (1958)
    • . Through Tuesday: 5 with two more a slam dunk, and potential for a few more by next Monday. And there's still August and early Sept. yet.
    • Hottest July on record (high temperature): 81.4 degrees in 1958. (If current 7 day forecast verifies exactly, our avg. this month will be 81.25)
    • Seattle daily records: Wednesday: 95, Thursday: 94. Friday: 93

    When Does It End?!?

    As I mentioned earlier, this pattern has the makings of the 1977 heat wave that stretched 18 days. We should begin some gradual cooling as we get into Friday, and by the weekend, highs should be into the upper 80s as this ridge slowly weakens. But a new area of low pressure developing off the California coast, it will keep pressures lower offshore and could keep the surge of marine air from rolling in until the middle of next week, meaning several more days of above normal temperatures, although not to these extreme levels.

    BUT! Cool weather fans, I present this to you:

    That may seem like squiggles and blobs, but what it represents, is bliss: At face value, that's a mostly cloudy day with a few showers and highs in the upper 60s or so.

    Only one slight problem -- that's not until next Thursday. It's circled on my calendar anyway.

  • Link:
  • 1 comment:

    Anonymous said...

    Nice! Now Antony Watts has a HOT competence.

    It would be good if for any "excepcionally cool weather" he posts, you post an excepcionally hot weather in some other place.

    PD: please, could you translate the temperature in degrees Farenheit (a scale used only in USA, Liberia and Myanmar) to the worldwide used Celsius scale?