A Very Dry Week When It Ought to Be Moist

The climate gods are being additional type to us this 12 months, offering a normally dry interval throughout the climatologically wettest time of the 12 months.

As an instance, right here is the climatological likelihood of receiving a hundredth of an inch or extra in Seattle over the 12 months.  The climatological likelihood of rain every day is over 60% from November 7 by way of mid-December.  That is sometimes the wettest time of the 12 months!

The forecast for this week?    Completely dry with loads of solar.   Check out the forecast precipitation complete by way of Saturday at 4 PM.  No rain over the Northwest and California.

The explanation for these dry circumstances?   The large West Coast ridge is again, as proven by an upper-level map (500 hPa, about 18,000 ft) on Tuesday round 4 PM.   The stable strains are heights, however you may consider them because the stress at round 18,000 ft. 

To get a greater view of the upper-level scenario, the next map is on the identical degree, with the shading displaying the anomalies from climatology (regular).  Purple colord point out above-normal 500-hPa heights and blue/inexperienced are the alternative.  

You may see our ridge has “bookend” troughs of low pressures/heights.   It is a very steady sample, known as an omega block.  We will likely be dry, however the japanese half of the U.S. will likely be chilly and moist.

It does seem that this sample is destined to breakdown subsequent Sunday, with the 72hr precipitation totals ending on Wednesday the twenty third being fairly soggy (see forecast beneath).

My recommendation…benefit from the nice climate this week, with highs within the lowlands round 50F.   It will not final.