Saturday, May 15, 2021

Weather Discussion for Saturday May 15, 2021

Normal high/ low temperatures for May 10-May 17 (high/low) Redding 81/54, Chico 80/51, Quincy 72/38, Chester 67/35, Susanville 70/39, Grass Valley 71/46, Weaverville 76/39, Mt. Shasta 67/40, Yreka 73/41, Alturas 67/33

This blog will be issued every Monday, Wednesday, and Saturday morning and updated if the weather is changing or critical or interesting weather events are occurring. 

The cutoff low pressure area is now over Northern and Central California and is moving southeastward. Scattered showers and thunderstorms will occur again this afternoon and evening over the foothills and mountains with isolated activity possible in the valley.  Temperatures will be cooler today.  Sunday most of the state will be sunny except over the Sierras south of Mt. Lassen, where isolated afternoon thunderstorms will occur.  

Monday and Tuesday look clear with temperatures back above normal.  Winds will be light.

Quite a change in the weather starting Wednesday.  A strong...for this time of year...low pressure area will be nearing the coast late Tuesday (see map below).  This system  will move slowly across the north state Wednesday and Thursday.  The low will trigger showers and thunderstorms.  Temperatures will be below normal.  Snow levels will be 5000 to 6000 feet.  Periods of gusty southwest to northwest winds will occur.  Friday looks partly cloudy over the areas north and east of the valley with a few showers.  Temperatures will continue below normal.  

Late Saturday and Sunday a weak system could bring showers over the areas from Redding northward.  

The Old Forecaster
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  1. in the 7:30 picture showing the LP cut off what would be the pressure chart that you would be looking at if the satellite was not available? And would the LP be visible at different pressure charts. Thanks

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  3. Back when I started working as a meteorologist we didn't have access to many satellite picture. In fact in the Redding office we didn't have routine pics till late 1980s. On a sfc weather map it would show up with the reported winds moving around it counterclockwise. Analyzed pressure lines would get lower as you move toward the center. As you move aloft the system would be less defined but still would show up.