Weather Forecasting!

[Jerry]

Anyone else look at the forecast computer weather models?

I started looking at weather and predicting weather from the age of 10 or so. Loved it ever since!

Anyways, I've been looking at a couple different models that run a couple times daily. The GFS, EURO, GEM and all of them point to a major pattern shift mid January... I've seen everything from frigid arctic blast of cold and snow, to ridging and dry like we've seen the last month or so. The long range models are completely baffled on what will occur with this pattern shift. This year we have a La Nina, and you wouldn't even know it based on our weather for the first 1/2 of winter so far. Historically, La Nina usually don't effect the overall pattern until the second 1/2 of winter though, so all is not lost, yet anyway... The cascades are not healthy with snow base right now. My guess is March will be a BIG month of snow up there though! There's no guarantee with predicting or forecasting weather, but what I would bank on is a wet cold spring.... So this year may be another year of high water springer fishing!

I will update this thread if I see any trend building on what happens with this major pattern shift.

[spactrukn]

Jerry, last year when you started saying the same thing a few weeks later all hell broke loose and we had major flooding all over Northwestern Oregon.

[Jerry]

Ya except I thought it was going to snow instead of flood. So it changes rapidly...new 00z GFS shows a modified arctic front that spills out into the pacific off the coast of Canada bc and rides the jet over the northwest. Lots of snow with this run, but again, the model changes when trying to forecast anything over 4.5 days. Not saying this run isn't what could happen, just haven't seen any consistency yet.

[Spade]

I'm hoping for a week or two of snow on the valley floor. I enjoyed that last time.

[Jerry]

Recent model runs of the GFS (Global Forecast System) have backed off for a various number of reasons, although now the EURO (Europe Model, which is favored by the pros over the GFS in the mid to long range) is showing a good setup for a healthy ridge to setup in a favorable position for an arctic intrusion of some sort.... Basically, all of them are flip flopping trying to figure out the pattern shift but the dynamics are too much for the computers to figure out at the moment.

[Jerry]

Quick update. The forecast models are still trying to figure out the upcoming pattern shift. The GEM (canadian model), Euro (Europe model), and the JMA (Japan model) all agree on a cold maritime trough that drops down the coast Saturday/Sunday and bring low snow levels and colder temps. On the other hand, the GFS (noaa's model) has been showing warm upper atmosphere temps and ridging. This would equate to fog in the south valley all day and fog/sun the closer you get to the gorge. The EURO has been rock solid 3 runs in a row and the 00z that ran last might showed snow showers on Sunday and 2-3inches of snow for Monday from about Salem to Bellingham...this model is one of the best, but Monday is 6 days away and anything more then 2-3 days out on these models in the pnw can change and dramatically. I will keep posting updates.

[Jerry]

The 12z GFS is coming around to the other 3 models now instead of being an outlier... details are still very much in the air, but ridging is looking more and more less likely. An active pattern and possible modified or arctic blast looks more reasonable at this point. This is likely to be a nail bitter the next few days until all of them hone in on the accurate solution. The 12z has an epic/snow and ice storm middle to end of next week, but we call anything past 4.5 days lala land in the forecast models.

[Jerry]

Alright... Evening update: 00z GFS is looking like a Jan 11-15 1971 type event. Basically anything that fallls Sunday through Thursday of next week would be snow at face value. This has the potential to change in many different ways, so nothing is set into stone. You will notice today/tonight alot of PDX mets on TV are starting to mention the possibilty of snow. They will be very conservative for fear of being wrong and in their line of work this is the most type of stressful weather to forecast. The power the local mets on tv hold is crazy. They mention the S word and the local grocery stores, tire shops, etc explode with a rush of people. The safest bet for them is to go with what local climatology suggest will happen rather then a climate extreme. The snow storm of 2008 was a once in 40 year event, so it's safer to forecast on the "safe" side and wait for the models to refine the details before they stick their necks out. If the models continue to show support of what's being shown now, we could be in for 4-10 day window of wintery precip chances.

Every day the National Weather Service releases AFD (area forecast discussions). The terminology and overall structure of these AFD's are pretty easy to follow even if you aren't an "expert" in weather terminology. Here's the latest AFD from this evening. It's important to note that if anyone is fishing the Gorge or any area influenced by east winds, get ready for some good wind the next couple days. The Vista house in the Gorge will see 80-90mph gust in the next 48 hours.

FXUS66 KPQR 110443
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
840 PM PST TUE JAN 10 2012

.SYNOPSIS...HIGH PRESSURE GIVING REGION BENIGN WEATHER CONDITIONS
FOR NEXT SEVERAL DAYS...WITH OFFSHORE FLOW INCREASING TONIGHT AND
WED. WILL SEE AREAS OF FOG...MAINLY IN THE INTERIOR VALLEYS NEXT FEW
NIGHTS. COLDER AIR WILL BE DROPPING SOUTHWARD OVER THE AREA SATURDAY
INTO SUNDAY FOR LOW SNOW LEVELS. AND AT LEAST THE FIRST HALF OF NEXT
WEEK LOOKS TO BE QUITE UNSETTLED.
&&

.SHORT TERM...NOT MUCH IN WAY OF CHANGES. THE SHORT TERM WILL BE
DOMINATED BY THE BUILDING UPPER RIDGE THROUGH THURSDAY AND INTO
FRIDAY AS SHOWN BE THE MODELS. THE INVERTED TROUGH DEVELOPING ALONG
THE COAST WILL WEAKEN BY FRIDAY. OFFSHORE FLOW SHOULD PRODUCE GUSTY
EAST WINDS ON THE WEST END TONIGHT THROUGH THURSDAY MORNING. THE
MAIN ISSUE IS HOW MUCH FOG IN THE VALLEYS. EXPECT THE OFFSHORE FLOW
TO LIMIT THE AREAL COVERAGE TONIGHT AND WEDNESDAY NIGHT...BUT MORE
EXTENSIVE THURSDAY NIGHT. DEVELOPING STABILITY IN THE VALLEYS CLOSE
TO RESULTING IN AN AIR STAGNATION ADVISORY...BUT EXPECT WILL FALL
SHORT OF THE DURATION CRITERIA. SS

.LONG TERM...THE LATEST EXTENDED MODEL RUNS CONTINUE TO KEEP AN
UPPER LEVEL RIDGE THROUGH EARLY THIS WEEKEND. THE PATTERN LOOKS TO
CHANGE SIGNIFICANTLY LATE SATURDAY INTO SUNDAY. MODELS ARE JUST
BEGINNING TO SHOW SLIGHT AGREEMENT ON A DEEP TROUGH DIGGING DOWN
OVER THE PACIFIC NORTHWEST FROM OVER BRITISH COLUMBIA THROUGH THE
WEEKEND AND INTO EARLY NEXT WEEK...POTENTIALLY SIGNIFICANTLY
DROPPING SNOW LEVELS OVER MUCH OF THE AREA. THIS TROUGH DOES ALSO
BRING PRECIPITATION BEGINNING SUNDAY...WITH A SECOND POTENTIALLY WET
SYSTEM MOVING ACROSS THE AREA MONDAY INTO TUESDAY. DEPENDING ON THE
STRENGTH OF THE TROUGH AND EVENTUAL EXTENT OF THE COLD AIR...THIS
PATTERN MAY RESULT IN SIGNIFICANT SNOWFALL ACROSS MUCH OF THE AREA
TO BEGIN NEXT WEEK...ESPECIALLY INTO THE CASCADES AND FOOTHILLS.
ALTHOUGH DETAILS WITH THIS CHANGE ARE STILL QUITE FLUID...IT IS A
SITUATION THAT BEARS WATCHING CLOSELY OVER THE NEXT FEW DAYS. BROWN

The 00z EURO will be out at 10:50pm, so I will post what it and the other models show tomorrow at some point. This could be EPIC, a BUST, or anything inbetween. But the evidence is building that chains and de-icer are in the near future.

[Arctic]

Good... The rivers are gettin low again, and the fish are on to me this time around! Could use a good precip event to blow everything out again... Why not? I like fishin the rise, when they start to hunker down on the banks... and then again as it falls back into high, but fishable shape!

[Jerry]

Quick update cause I'm awake and can't sleep. The euro is even more bullish with the cold trough and digs it further south. This model also holds onto the cold pattern out to day 10, so it could be a long cold spell with multiple chances at snow. The euro was the model that was the moat consistent when all the others were flip flopping. The GFS was the first to pick it up, but then couldn't catch onto what the euro and gem were seeing. The reason I want to bring this up is the GFS think we moderate around 216 hours, while the euro has us still sitting in the cooler at 240 hours out. Which is the winner? Your guess is as good as mine. Hopefully (if you like cold and snow) the GFS is wrong about warming is up quicker. This is getting to the point where I'm starting to get excited about the Sunday-Wed Tim frame. We could see an epic winter storm and it would be awesome to fish some rivers with the snow falling.

Stay tuned.