The Last Heatwave of the Summer season? When does the menace disappear?

 Even with cool temperatures this weekend, the specter of extra heat is on the horizon.

However is that this the tip of the specter of actual heat in our area?   

Let’s begin with the forecast.    One other ridge of excessive stress will construct over the West Coast on Monday and Tuesday, as illustrated by the higher stage (500 hPa stress, about 18,000 ft) map for Tuesday at 5 PM.  The crimson signifies larger than regular stress, the blues and purples under regular (troughing.

The newest Nationwide Climate Service Nationwide Mix of Fashions temperature forecast for Seattle indicated highs within the higher 80s on Tuesday and Wednesday earlier than an prolonged cool-off to extra seasonal temperatures round 80F.  Importantly, lows will reliably decline into the 50s, guaranteeing an excellent night time’s sleep.

As obvious to all of you, the nights are getting longer, the times shorter, and the energy of the solar’s rays is ebbing.   Finally, we merely will not be capable to get into the 80s and 90s anymore.   

However when?  What does climatology inform us?  

To help on this evaluation, let us take a look at the climatology of temperatures on each side of the Cascades for late summer season and early fall (August 1- November 15, see under).  Every plot under reveals the report highs (reds) and lows (cyan) and the typical excessive/low vary (brown shade).  I additionally plotted this yr’s temperatures (blue bars) and famous the 80, 90, and 100 F ranges with dashed strains.

For SeaTac Airport, temperatures have gotten above 90F many occasions in August and early September, however by no means after October 1.  Highs above 80F have occurred by means of mid-October.    

The underside line, the specter of above 90F in western Washington will likely be over in a month, with little likelihood of temperatures exceeding 95F after Sept. 1.

For the Tri-Cities (Pasco proven under), getting above 100F isn’t any massive deal in August, however turns into unprecedented after the primary week of September.  Reaching into the 90s has occurred many occasions in September, however turn out to be unprecedented in October.  October is a really month in jap Washington.

The underside line:  Based mostly on the present forecasts, it seems that after mid-week, there may be in all probability little likelihood of Seattle exceeding 90F for the remainder of the yr.  And after Friday, little likelihood that Richland will exceed 100F for the rest of 2022. 

Reminder: I will likely be educating ATMS Atmospheric Sciences 101 this fall.

Like final yr, I’m educating atmospheric sciences 101: a normal introduction to climate and local weather, this fall. You’ll be able to be taught extra in regards to the class on the class web site. I discuss every thing from the fundamentals of the environment to climate prediction, thunderstorms, hurricanes, and native climate to international warming and local weather.

I will likely be educating the category in particular person on the UW, however may even make it accessible over zoom. Thus, of us can take it remotely.

Have You Been Censored by the Seattle Instances?

I’ve turn out to be conscious of a major problem on the Seattle Instances:  they’ve been censoring individuals who have left feedback with a distinct viewpoint on local weather change than theirs, with their actions based mostly on accusations of “local weather misinformation.”   When you have been censored by the Seattle Instances, together with removing of feedback or locking of accounts, please let me know by means of e mail or as a touch upon this weblog (I can’t evaluate your identification).

This can be a very critical challenge and displays a disturbing angle at our native newspaper.