Hailstorms and Rainbows

May 5, 2010

Check out this picture!  Good size hailstorm moved through Salem around 4pm today.  One of our viewers sent in this picture of the highway totally covered in round, slippery, icy hailstones.  Easy to slide in this stuff.

Apparently that storm had quite a bit of cloud to cloud lightning (from another email), but no cloud-ground strikes.

Still a couple more hours of action and then it’s just on to a chilly night and much warmer/drier days.

Josh Sanz shot this picture over Camas this evening

9pm Update:  The big showers are gone, but I sure received a slew of rainbow pictures this evening.  My co-worker Robin Sanz sent this beautiful picture her husband took a half hour ago or so.  He used to be a photographer at KOIN, so he obviously has some skills I don’t have when it comes to setting up a shot!

For tonight I have a few thoughts.  First…I think it’s very strange to have a Frost Advisory when the forecast lows for Kelso, Portland, & Salem are all well above freezing.  Now if the wording in the advisory clearly stated that only the outlying areas would see frost (like with a 1,000′ snow level advisory) it would make more sense.  I think the only areas that see frost tonight may be the westside and up north in central/northern Clark County.  That’s mainly due to expected low clouds developing after midnight.  Our RPM and the WRF-GFS, the two best mesoscale models I have access to, both show low clouds “back-building” across the metro area after midnight.  Our RPM says all the area will be clouded in by 5am, with the only clear spots right up against the Coast Range.  I had ignored our model earlier, but once I saw the WRF-GFS showing the same thing, it increased confidence quiet a bit.  And there is plenty of moisture left on the eastside.  Showers are continuing in central/eastern Multnomah county and eastern Clark County this evening.

A very nice warmup is still on tap.  We’re headed back to normal or slightly above only…no dramatic warming expected in the next 5-7 days.  00z models now show a slightly better thermal trough west of the Cascades all day Friday and the first part of Saturday.  Offshore flow + 850mb temps 5-7 degrees easily means 70 degrees here in Portland.  My May chart shows somewhere between 68 & 75.  That’s why we upped the high for Friday to 70.  Saturday may be as well if the flow doesn’t turn onshore too quickly.  So “normal May programming” is on the way!

Chief Meteorologist Mark Nelsen

No Frost, But Snow in the Hills This Morning!

May 5, 2010

Check out this picture…snow sticking down to around 1,000′ along Highway 26 at Brightwood this morning.  Some heavy showers are moving through Clackamas County, dragging the snow level down very low there.  Brrr!

At least the cloud cover and showers kept the entire metro area above freezing last night.  I don’t see the frost point reached at any of the usual cold spots.