Warm & Humid Weather, and maybe a Thunderstorm

A quick check-in this afternoon. 

Today is the 5th day with above average temperatures here in Portland; it’s the first time we’ve had 5 consecutive warmer than average days since early March!  It shows how unusually cool spring and the first half of summer was.  The payoff has been the last 10 days as we’ve made quite a turnaround into typical summer conditions.    In fact this morning’s and yesterday morning’s lows (64 & 65 degrees)  were the warmest of the summer, due to quite a bit of moisture in the air.  It sure hasn’t been extremely humid even for us, but the air definitely has a “heavier” feel to it.

I see thunderstorms firing up over the Cascades and even some lightning strikes well offshore late this morning and into the afternoon.  We sure have the warm and humid conditions that make it “feel thundery”.   There is a very obvious upper level disturbance near Brookings at this hour, and it’s headed right up through Northern Oregon and into Washington overnight.  With nice lifting, lots of moisture to work with, and a warm airmass (no cool marine air to stabilize things), this CAN be a great setup for an overnight thunderstorms.  The curious thing is…none of the mesoscale models show anything to “write home about” the next 24 hours.  Generally they do quite well with this pattern, although a similar setup on Monday, July 25th gave us the surprise morning thunderstorms.  I would prefer to see a more southerly to southeasterly flow to give us nocturnal thunderstorms as opposed to the current south-southwest direction, but those late July storms came out of the southwest as the disturbance moved overhead.

So it boils down to “we MIGHT see a thunderstorm during the next 14 hours, but don’t get your hopes too high”.  That’s for west of the Cascades.  In the Cascades and eastside it’s a far more impressive pattern.  The latest mesoscale discussion from the Storm Prediction Center says “FAST MOVING MULTICELLS…AND PERHAPS A FEW SUPERCELLS…ARE EXPECTED ACROSS ERN/CNTRL ORE AND FAR SRN WA THROUGH THE REMAINDER OF THE AFTERNOON INTO EARLY NIGHT. ISOLATED DAMAGING WIND GUSTS AND LARGE HAIL WILL BE POSSIBLE WITH THE STRONGER STORMS. GIVEN THE LOW POTENTIAL FOR WIDESPREAD SVR…A WW WILL PROBABLY NOT BE NEEDED…BUT CONDITIONS WILL CONTINUE TO BE MONITORED.”

Hopefully we will see some excitement west side tonight since I’m not working this week and I can relax/enjoy from home like everyone else!  Otherwise enjoy the “sultry summer weather” since we’ll be back to the usual programming (clouds and cool) in no time at all I’m sure…September is only 1 week away.

Chief Meteorologist Mark Nelsen

312 Responses to Warm & Humid Weather, and maybe a Thunderstorm

  1. pappoose in scappoose says:

    New post

  2. chiefWright says:

    Aha, Mark, you’ve surfaced! Seem’s like most of the PDX WX prognosticators got caught a bit flat-footed. Chance of Tstorms were in the forecast, but seems pretty weak for the best show we’ve had all summer. What’s your thoughts about last night?

    • Mark Nelsen says:

      For the valley it was a great show, but I have a feeling most people in the central/northern/western parts of the metro area slept right through it.

    • Ryan (Walnut Grove) says:

      I know I did… I woke up about 5am and ran outside but saw nothing to the south.

      I was just too far north.

    • Ryan (Walnut Grove) says:

      I think the important thing to note with weather forecasting is that just because a portion of the valley was affected doesn’t mean the vast majority of the forecast area missed out on the fun.

      It seems that the only eastern and southern portions of the metro got the experience so Mark’s forecast when you take into account the entire forecast region was accurate.

  3. Cherie in Vernonia says:

    my dearest friend lives where the + sign is! Might not be hearing from her for a few days!


  4. Runrain says:

    Gotta love the NWS discussion this morning stating that this mornings storms occurred as expected-ha! Sorry guys. Not even CLOSE!!

    • pappoose in scappoose says:

      Hahaah! Looks like a CYA statement to me Mark!

      National Weather Service Portland or
      830 am PDT Friday Aug 26 2011

      Right now believe the thunderstorms Saturday afternoon and night will stay east of the valleys but a slight deviation in the track could change that.

  5. pappoose in scappoose says:

    I really like the mama…no, mamary…no, O, I just like the name of these!


    • Austin (Cornelius) says:


    • pappoose in scappoose says:

      Beats me Austin, I’m not in the prediction business, there are enough folks debating that point already. I have way more fun nit-picking/making fun of the forecasts of all the dedicated people who do put in the time to provide us with the benefit of their weather knowledge (which I GREATLY appreciate).

      On the other hand I’m absolutely certain another herd will wander in…just don’t know when. Hahaah!

  6. pappoose in scappoose says:

    Was quite a STAMPEDE.

  7. chiefWright says:

    OK, I gotta scoot here, but a couple more pix of the morning. Here’s looking NE. Check out the mammutus:

    And to the S. There’s a very faint, but definite rotation in this cloudmass:

    Both cells are still sparking & grumbling, but very fitfully.

    Tahnks for the company this fun morning!

  8. I’m enjoying this remotely. . . . Sure hope those cells hold together and make their way up here. . .

  9. chiefWright says:

    Just saw a pretty CG strike from that cell S. of Estacada

  10. A new storm has flared up south of Silverton….

  11. chiefWright says:

    All calm now. Beautiful morning outside; cool & fresh. 0.15″ in the bucket. Some showers visible to the E and S.

    • Austin (Cornelius) says:

      did you know lightning cant strike in one spot twice? (myth) the video shows lightning striking one spot about twelve times, fairly close or on the spot.

    • chiefWright says:

      Ohboy, it ain’t over ’til it’s over. I see– and hear– something brewing up to the S, and radar confirms something developing over the Waldo hills.

    • Austin (Cornelius) says:

      the radar isnt updated so i cant confirm

  12. Austin (Cornelius) says:

    hey mark? what is the link to the live radar? aka, the one you use in the newsroom, i did it before but you guys rearranged the site so i cant find it.

  13. Doppler Dave (NE Portland) says:

    I saw a few flashes to the east and southeast while getting ready for work this morning, and heard a couple of distant rumbles of thunder.

  14. chiefWright says:

    And here’s looking to NE. Winds now calm. Whatever it was has moved on. Out to check the rainbucket….

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