Mariposa projected high temperature for Wednesday: 93 degrees
Oakhurst projected high temperature for Wednesday: 95 degrees
Yosemite Valley projected high temperature for Wednesday: 85 degrees
June 18, 2019 - The National Weather Service Hanford Office reports a recurrence of widespread triple digit heat is likely in the San Joaquin Valley this afternoon.
Prolonged exposure to triple digit heat can pose a health risk to the elderly, persons with respiratory ailments and anyone who is not yet acclimated to hot weather.
If you’re going to be outdoors during the hottest time of the day (between 1 pm and 6 pm), avoid strenuous exercise, stay hydrated and wear light colored, loose fitting clothing.
Remember that going from hot air temperatures into cold water in area rivers could cause shock to the body and lead to drowning.
Use caution if entering local waterways and remember to wear a life vest.
Area Forecast Discussion National Weather Service Hanford CA 355 AM PDT Wed Jun 19 2019 .SYNOPSIS...Dry weather will prevail over the district during the next 7 days. Temperatures will average well above normal today. A noticeable cooling trend Thursday through Friday will be accompanied by gusty winds through and below the mountain passes. The weekend will bring lighter winds and slightly warmer afternoon temperatures. && .DISCUSSION...A hot day is on tap for today but it should be the last day of triple digit heat in the San Joaquin Valley and the Kern county desert for at least the next 7 days. We`ve been pretty fortunate so far this year that there`ve only been a handful of days at or above the century mark in the San Joaquin Valley and the spells of hot weather have been relatively short. We all know it could be much worse. Two years ago this week we were in the midst of a 9-day stretch of triple digit heat and on five of those days, high temperatures in the San Joaquin Valley were above 107 degrees. During the peak of that relentless heat wave, thermometer readings spiked to 110 degrees in Fresno and Bakersfield! Highs today will again flirt with the century mark as a ridge of high pressure aloft centered over the Eastern Pacific noses into central CA. After today, this ridge will shift far enough westward to allow room for an unusually deep upper level trough to drop southward out of western Canada into the Great Basin. The majority of the models track this trough as an inside slider. However, the 06z run of the GFS forecasts this system to track a bit farther west than the other models Friday. If this were to happen, it could bring showers into the high Sierra Friday afternoon and some mid level clouds as far west as the eastern San Joaquin Valley by Friday evening. That`s a new development from earlier GFS runs and for now we`re going to discount it unless the remaining models trend similarly. What we`re most confident of is the big change to refreshingly cooler weather later this week. Ironically it will arrive here Friday, which is officially the first day of Summer. The cold front that ushers in this cool change will be moisture starved and equipped with little more than some mid and high clouds as it sails southward through the CWA during the midday hours Friday. Prior to its arrival, westerly winds will increase through and below the passes Thursday afternoon and evening. Those breezes will continue through Thursday night then ramp up again in the wake of the cold front Friday afternoon. During this period, winds could kick up some dust on the west side of the San Joaquin Valley. In the Kern county mountains and desert, westerly winds might gust up to 50 mph right below the passes, especially Friday afternoon into Friday evening. Otherwise, high temperatures will trend downward significantly after today. Afternoon temperatures Friday will be no higher than the 80s in the San Joaquin Valley, lower foothills and the Kern county desert. The nights will be comfortably cool, too, later this week with lows in the 50s outside of the urban areas of the San Joaquin Valley and over much of the Kern county desert. Afternoon temperatures will bounce back to seasonable levels this weekend as the upper level trough moves out of the Great Basin and the Eastern Pacific ridge begins to build back into the Golden State. Sunday will definitely be the warmer day of the weekend after a residual cool start to the day. A day to day cooling trend may become re-established over the CWA early next week as yet another upper level trough settles southward out of western Canada. By next Wednesday, a robust onshore flow could bring ocean cooled air inland and keep high temperatures below 90 degrees over much of the San Joaquin Valley.Source: NWS
