Don’t let the door hit you, April bluster.
The cool, damp April we’ve experienced in the Walla Walla Valley over the last two to three weeks will see an end to its reign this week as resurgent high pressure shoves aside lingering fronts and areas of low pressure and shunts all of that unpleasantness to the east, where folks in Idaho and Montana can enjoy it for a while.
Though a dazzling display of blooms on our local trees and flowers speaks of a warm-weather scenario, this month’s seemingly never-ending suite of subfreezing nights and cool, blustery days has been more appropriate for late February or early March. Your weatherperson — among many others — has grown tired of this April’s irksome antics and is eager to move along to the sort of milder regime that we can normally expect here in the Valley this time of year.
All of us engaged in agriculture in southeastern Washington are extremely grateful for last Friday’s soaking rain, which deposited almost two-thirds of an inch on the Walla Walla Valley. An additional tenth of an inch late Sunday was the icing on Friday’s cake. Your forecaster’s grapes at Walla Walla Community College are on the verge of bursting forth with their new spring growth, and that water combined with the warmer temperatures we'll be seeing this week — after one final very chilly morning today — will certainly encourage that process.
High pressure will be building over our region over the next several days, and afternoon readings should warm a few degrees each day under the subsiding air beneath the high. This subsidence will also guarantee a rain-free stretch of days as precipitation will occur only in air that is being lifted and cooled by some mechanism.
Highs may reach the mid-70s by Friday under mostly sunny skies and generally light winds. Yes, your forecaster is well aware that he alluded to temperatures closer to the mid-80s in a previous column. But that pronouncement can be attributed to what former Fed Chairman Alan Greenspan would call “irrational exuberance” — a commodity your prognosticator has in large supply.
As we head into the coming weekend, however, all bets are off. The two main forecast models we use are currently cat-fighting like Nikki Minaj and Mariah Carey on “American Idol” — all of which provides great entertainment in both cases, but does little to further our understanding of either the weather or the singing involved.
The Global Forecast System model actually strengthens the existing high and holds it well into next week, suggesting high temperatures that approach the heretofore unheard of mid-80s.
Meanwhile, the European Center for Mid-range Weather Forecasting outlook plays Scrooge to the GFS’ take on next week and brings a cold front through our area on Saturday night, pushing readings back down into the 60s on Sunday and for the beginning of the following week. The problem is, both models are very inconsistent in their run-to-run forecasts, so it is very difficult to extract even a small degree of certainty from either of these warring parties’ outlooks.
In such cases, the smart thing to do is to keep a close eye on both and see which one blinks first and gives in to the other’s way of thinking. Who said weather forecasting was boring? Here we have ample proof of it being part UFC match, part liars’ dice game.
The early line would favor the ECMWF’s cooler forecast, given what we have seen the last couple of weeks. On the other hand, it can’t be 61 and cloudy indefinitely — particularly as we fade from April into May, so the truly intelligent money is on the speedos-and-suntan-lotion scenario favored by the GFS. Let the best forecast model win, and shame on the loser!
A lifelong fan of both the weather and the Baltimore Orioles, Jeff Popick teaches at the Center for Enology and Viticulture at Walla Walla Community College and manages the school’s teaching vineyard. Send questions and comments to firstname.lastname@example.org.