July Chill & Showers Ahead

July 15, 2010

Just for fun, let’s take a look at the “spaghetti” charts for next week, specifically Tuesday morning.  The image below is the output from this morning’s ECMWF (the EURO as we like to say) Ensembles.  Those are just slightly different variations of the main model run that also run at the same time.  Basically atmospheric modeling people perturb the intial conditions in the model 20 different ways, then run it 20 times (an ensemble of runs).  I’m not sure if that’s exactly the number of ECMWF runs, but I see a lot of lines! For that reason you’ll want to click on the image to get a better view.

Focus on the red lines.   Each one is the 576dm line on one of the ensemble runs.  Here’s the reason we use ensembles;  to get an idea whether the operational model run is an “outlier” or if they all generally agree.  In this case…the cool trough dipping down over the Pacific Northwest next week…they all agree.  This is pretty good agreement for 5 days out.


Now check out the GFS ensembles from this morning (for Tuesday again)…

Note the same general pattern.   This is a much easier graphic to read.  The line we’re following this time is the 582dm line, that’s why it’s located a bit farther south.  You could imagine the 576dm line is a bit north, about where the other map showed.

The big picture on both models shows the same thing:  A chilly week (for the hottest time of the year here) is ahead as a cool trough descends on the Pacific Northwest.  I seriously doubt the entire week will be cloudy and cool,  but apparently I made the wrong choice on vacation dates. 

Each year here at KPTV we submit our yearly vacation requests in December;  I did mine during that cold spell last December.  The real hardcore FOX-12 viewers probably notice I tend to take most of my vacation time in July and August.  I like to have warm and sunny weather when I have days off since I am naturally an “outdoors” person.  I couldn’t imagine a week off in January, sitting around the house hiding from the rain.  That plus our active weather season here is November through February means it’s best to take time off during the deadest weather time…mid-summer.  So there I was in December, thinking that I should avoid the week after July 4th because it might “still be cool and wet”.  So I chose 3 different weeks starting next week and running through the 3rd week of August.  Well, the first one is going to be a bust. 

We’ve added showers to the forecast next Wednesday-Thursday due to a pretty good trough and very chilly air at that time.  The ECMWF holds off the best chance for showers until the end of next week (more like Saturday).  Either way, by putting showers in the 7 Day I want to make it clear that those of you getting a new roof or with hay on the ground (just some examples) should be ready for a chance of showers by midweek.

Chief Meteorologist Mark Nelsen

Steve Pierce in the Top 3!

July 14, 2010


Looks like our own Steve Pierce is a  bit more famous.  No beach party is coming to Vancouver, but the Pierce family was SO close!

 Here’s the press release we got from The Weather Channel today:


The Weather Channel Announces Finalists
for Its ‘Ultimate Summer Beach Party’ Contest


Contestant from Vancouver, WA, crowned Contest’s Fan Favorite


ATLANTA – The Weather Channel® (TWC) announces three finalists for its “Ultimate Summer Beach Party” contest.  Contest finalists include Susan Adair of Kent, OH, Steven Caldwell of Terre Haute, IN, and Steve Waldner of Fargo, ND.  In addition to announcing the finalists, Steve Pierce of Vancouver, WA, was crowned as the contest’s fan favorite, where users voted on their favorite video submission.  Click here to watch his video.


A panel of judges from TWC viewed hundreds of video submissions and, based on uniqueness and creativity of the submissions, selected these finalists, one of which will be chosen as the grand prize winner to host TWC’s “Ultimate Summer Beach Party,” live July 25, from 8 a.m. – 2 p.m. ET. All of America can tune in as TWC transforms the winner’s home into a beach party destination complete with sand, water features, palm trees, barbecue and much more. Meteorologists Jen Carfagno and Adam Berg will provide on-air reports to capture all of the day’s excitement and get reactions from the winner along with family, friends and neighbors.

To be eligible, contestants submitted a short video describing why they deserve to host TWC’s “Ultimate Summer Beach Party.” From interesting stories to unique props, these finalists caught the attention of TWC judges. To view their videos as well as other submissions, visit www.weather.com/beachparty.


All finalists and fan favorite will each receive a TWC summer-themed prize pack valued at $250, which includes an HD flip camcorder.  Viewers can tune in Sunday, July 18, during “Weekend View” to find out who will be selected to host the biggest beach party on the block – no matter the location.

A Cool July?

July 13, 2010

It’s looking likely that July will either be near or below average temperature-wise.  Sure, we’re just barely halfway through, but all long range models agree that a trough (dip in the upper-level flow) will develop near the West Coast later this weekend and linger at least through next week.  In fact 850mb temps down in the single digits are likely at some point…more like early June than the latter half of the hot month of July.  Here’s a CPC 8-14 day outlook:  It’s a bit blurry, but if you click on the image you’ll see the effect of a hot ridge in the middle of the country and that upper-level trough off the West Coast.

Of course in the short term we have a brief warm up.  The strong onshore flow has really decreased; the PDX-GEG gradient has dropped from around 16 millibars yesterday evening to 3-4 this evening.  Gorge gradient has decreased as well.  By morning it should be just about flat.  Combine that with 850mb temps that go from +2 this morning to +12 tomorrow AM to +16 Thursday spell a signficant warming in mid-July.  Probably no low clouds in the morning west of the Cascades, or at least very minimal coverage.

The onshore flow returns Friday, but isn’t very strong until Sunday night since upper-level heights will remain high.  I have next week off…getting concerned that I may need to head east of the Cascades for a sun fix!

Chief Meteorologist Mark Nelsen

A Chilly July Airmass

July 12, 2010

A very interesting weather day across the Pacific Northwest.  A huge marine push last night, then a cool airmass plunging through the region bringing high winds to the east end of the Gorge and eastern Washington/Oregon.  Peak gusts of 50-60 mph in the eastern Gorge are unusual in July even there.  Today’s events were similar to a September cold front east of the Cascades.  Dewpoints are way down as well, not just eastside but westside.

To give you an example of how unusually chilly today was; consider it was partly-mostly sunny the last third of the day…and we STILL couldn’t make it to 70 at PDX.  The 850mb temp (temperature in celsius around 4,000′) over Salem this afternoon recorded by the weather balloon was only 6.4 degrees.  I checked our chart which includes all July days from 1997-2008.  That’s over 300 days; Today was around 285!  There have only been about 15 July afternoons out of 300 that were this cool.

Now that we have mostly clear skies and low dewpoints, temperatures are dropping like a rock.  40s will be widespread by morning with even PDX possibly approaching the record low of 48 degrees.  With such a chilly airmass overhead we won’t get the solid low clouds in the morning, more broken again like the 2nd half of today.  Still, maybe we can squeeze out a few degrees of warming.

Much better Wednesday and Thursday with higher upper-level heights as the cool trough moves east.

The BIG picture (3-10 days out) shows some sort of longwave trough lingering over the West Coast, possibly deepening gradually beyond the weekend.  That screams average to below average temps, but probably no rain.  Those of you looking for a mid July heat wave are out of luck!

Trip Report: Wayne Garcia, Shauna Parsons, and I spent three days up at Timothy Lake this weekend.  That was along with our 6 kids and spouses of course.  That was a lot of fun.  I’ve spent plenty of time at Trillium, Clear, and Lost Lakes, but never Timothy.  If you like mountain biking, the round-the-lake trail is a wonderful ride on a 75 degree day.  Maybe 15 miles or so, although I added a few miles by heading up on the pavement through Little Crater Lake campground.  Nice to jump in the lake afterwards.  Nobody got hurt, except my son flying off a dirt hump jumping his bike.  No more flip-flops while BMXing!  Weather was that perfect Cascade camping temperature…75-80 daytimes and maybe 50-55 at night.  Glad we weren’t there for the windy 60 degree temps today!

Chief Meteorologist Mark Nelsen

The Hot Temps

July 8, 2010

Here are the “official” high temps around town today.  These are the NWS/FAA locations with ASOS sensors.  They are all well-sited out in the open and away from “heat sources”.  There is a common problem with home weather sensors (including mine with gets a bit too much morning sun).  It’s really hard to measure temperature correctly and it’s very easy to get too hot of a temperature.  You generally don’t get “too high” of a windspeed or “too much rain”, but temperature is a different creature.  If your temperature was more than 2-3 degrees from these you probably have your thermometer in a warm place, or it just might read warm in general. Your sensors must be away from pavement, walls, roofs, decks etc…keep in mind that one of those objects/surfaces 20 feet “upwind” can give you the same effect.  I see the “Rivergrove” on MADIS and “Liberal” were 112 and 108!  Those are extreme examples.  But I see one location in Washington County where two sensors read 97 & 98 and then another one nearby was 102.

One other thing to keep in mind; I notice most home weather sensors mention in the specs that the resolution could vary 1-2 degrees…another reason to always check yours against an official location near your home.

No Record So Far, but Hot!

July 8, 2010

An appropriate picture for today don’t you think?  This is Maximus (seems appropriately named), the 166 lb. dog jumping into the sprinkler water stream.  This is what summer is all about!  Thanks to Melissa Lapuyade-Gonzales. 

As of 5pm, the high temperature at PDX was 97.  BUT, that’s also the current temp…seems very likely we’ll notch up at least one more degree between now and 7pm.  I’m guessing 98 or 99 degree high in the end.  Hot!

Some buildups over the Cascades to the southeast.  Closest lightning strikes have been over Santiam Pass.

Chief Meteorologist Mark Nelsen

Hottest Day Today

July 8, 2010

Everything still on track for a very hot day today…upper atmosphere has warmed a bit, plus offshore flow is still lingering over the Cascades.  That easterly wind is much weaker this morning, so a widespread easterly wind is not in the cards for the metro area, but the effect will still be there to maximize heating.  I notice Corbett was the warm spot last night…it didn’t get below 70 degrees last night with the wind keeping the air stirred up.  That’s quite a turnaround considering a few days ago they had a tough time even getting ABOVE 60 degrees for a high!

A few obvious changes today will make it feel hotter: lack of wind for one, and then take a look at the picture above.  Low clouds have pushed inland as far as the Longview/Kelso areas.  That with the loss of the dry wind from the east means signficantly higher dewpoints; it’s going to be more humid.

You can see some thunderstorm leftovers in the South Oregon Cascades…I doubt that moisture makes it farther north than the Three Sisters today…but some good action down around Crater Lake!

Chief Meteorologist Mark Nelsen