We begin a rather hot stretch of weather — yes, even warmer than we’ve been — starting Tuesday as ridging builds aloft. Downslope flow from the northwest will act to warm the air as it sinks as well as help to keep the seabreeze pinned closer to the coast, which will help drive air temperatures well into the mid-to-upper 90s across the area after an already warm start in the upper 70s to around 80° at the coast. Mix in humidity and you’ll find heat indices across the area ranging from about 105-110° during the height of the afternoon. We’ll be in this heat index “danger zone” for a few days, so be sure to take it easy if you have to be outdoors during this time, and get lots and lots of water.

As the ridge builds aloft, this will also help to put a lid on afternoon thunderstorms for the most part; a shower or storm can’t be totally ruled out, but don’t count on one for any sort of heat relief.

Finally, Canadian wildfire smoke will add a milky haze to the overall sky composition. Upstream observations suggest that there could be some minor air quality impacts, but so far no major issues are anticipated. Stay tuned, though.

Rest of the work week: Turning much hotter

We turn even hotter heading into Wednesday and the second half of the work week. Highs will top out in the upper 90s each day with nary a shower or thunderstorm to cool things off until maybe Friday as the ridge begins to weaken some. Heat indices will continue a deep run into the danger zone each afternoon, particularly on Thursday and Friday when they may exceed 110° in parts of the metro at peak heating. Heat advisory criteria from July 1 and beyond is a heat index of 110-115° for two hours. (Beyond 115°, we get into Excessive Heat Warning territory.)

And while the high temperatures will grab a lot of the headlines, let’s not forget to look at the lows as well, which will only bottom out in the upper 70s away from the coast, where it is conceivable we may not get below 80° for a few days. Indeed, even the NWS forecast at the airport has a low of 80° on Thursday, which would tie the record warm low temperature set in 2001. We’re just not going to get much in the way of recovery from the very hot afternoon temperatures, so please do take it easy and try to spend as much time as you can in air conditioning.

As we head into the weekend, the ridge will weaken, breaking the stretch of excessive heat and bringing shower and thunderstorm chances back into play each afternoon. Hang in there…

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