Tired of the rain and cool temperatures? A major change is about to occur: the development of a "Super Ridge" of high pressure aloft over the northeastern Pacific.
This "Super Ridge" will bring a short period of spring-like warmth to some lucky folks in our region.
I am going to show you a series of forecast upper-level weather charts that describe the situation around 18,000 ft (heights of the 500 hPa pressure surface above sea level will be shown). You can think of these figures as describing the pressure variation at 18,000 ft. The colors indicate the difference from normal (red--above normal, blue--below normal).
Today, at 4 PM, the ridge of high pressure is found just inland from the West Coast, but with low pressure offshore. Since sinking air and dry weather are found under and east of such high pressure aloft, we arestill open to Pacific moisture that will push in later today and Thursday.
But high pressure is not done with us! By Tuesday at 4 PM, another high-pressure ridge builds over our region (see below).
This high pressure will be associated with warming air aloft and its surface reflection to the east will result in easterly flow over the Cascades, with downslope warming over the western slopes of the Cascades. To show this, below is the predicted surface temperature map for 3 PM on Tuesday.
Wow. Temperatures will rise to around 60°F on the western slopes!
Even locations away from the slopes will be warmed...just not as much. For example, the European Center model predicts a temperature of 59°F on Tuesday (see below). That will feel very nice.
But this is only a taste of the upcoming Super Ridging. By Friday morning, an absolutely extraordinary ridge/high-pressure area will form to our north (see below). This pattern produces absolutely dry conditions over our region.
I have some confidence in this projection because all the major weather modeling systems are forecasting something like it.
Want a sample?
Here is the 72-hour total precipitation ending Sunday at 4 PM. NO PRECIPITATION ANYWHERE.
I hope those pushing a drought narrative will wait before ringing the alarm bells.
Models forecast precipitation the following week, and the extended forecasts are for wetter than normal conditions over the next three months (see the European Center prediction below).
Even the Drought-loving U.S. Drought Monitor has backed off the drought alarms (see their latest graphic below), with drought gone over western Washington and "severe" drought only over the far southeastern side of the State.
Super Ridge
Impressive warmth for January! It will be a nice change from all the gray, gloomy, and wet we've been having.
ReplyDeleteSince the beginning of the water 'year' in October, Yakima has recorded 3.73 inches of rain. Normal is 2.84 inches over that time. Someone is going to have to explain to me how this qualifies as any kind of drought.
ReplyDeleteMost likely based on a longer period. A single recent rainy period is not enough to affect the longer term record.
DeleteThe Yakima watershed is also at 51% of its historic snowpack currently, so if those conditions persist that will necessitate "drought declarations" for agriculture, which are part of the legal process for instituting water rationing.
DeleteAlex...if the reservoirs are full or above average in spring, no need for drought declaration even if snowpack is below normal...cliff
DeleteCliff... In a normal year the Bureau of Reclamation delivers ~2.3 million acre-feet to through the Yakima Irrigation Project. The when full, reservoirs hold ~1 million acre-feet, so the majority of the water used in the area is stored via snowpack. It's entirely possible for the reservoirs to be above average come spring, but for low snowpack to necessitate a drought declaration.
DeleteAny chance of windstorm as this super ridge high of pressure moves out. Bigger question sometime what weather conditions lead to hurricane force winds in the Straight of Juan de Fuca, Whidbey Island, Skagit County...
ReplyDeleteI hope not! The coast has had quite enough wind this weekend!
DeleteHallelujah! We definitely need a decent break here in the north Cascades headwaters. The rain-year to date as of this morning is a whopping 46.11" (2.27" for the 24 hrs this morning, and it's still raining). I'm glad that the "Drought Monitor" crew has finally caught-up a bit. Alals, given the way those folks tot-up data I expect the "7-day" figures (and the map) will return to crisis mode, whatever the "water supply" reality, anywhere.
ReplyDeleteYou've had 46.11 inches of rain so far this rain-year? Thats impressive! If you don't mind my asking, what is the normal amount of rain you typically get in a rain-year?
DeleteCliff, I enjoy all of your posts, even the times you are way over my head. How about an entry that is just fun? Next weekend, Jan 17th and 18th, we will have 4 NFL playoff games. All 4 will be in outdoor stadiums where the January weather can get a tad nasty. How about a blog forecasting and comparing the upcoming weather for Foxborough, Chicago, Denver, and Seattle?
ReplyDelete