Saturday, May 28, 2016

Weather Discussion for Saturday May 28, 2016

Normal high and low temperatures for May 23-May 30 (high/low)...Redding 85/56, Chico 84/53, Quincy 75/40, Chester 71/38, Susanville 73/41, Grass Valley 73/47, Weaverville 78/42, Mt. Shasta 69/41, Yreka 75/43, Alturas 72/38 

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

High pressure is along the coast and will begin to build and move eastward.    The high pressure area will be over the west coast by Tuesday and Wednesday (see map below) and should hold there through the weekend.  The north state will be mostly sunny for the next week with warmer temperatures.  Temperatures will be running 10 to 15 degrees above normal and the north valley will see its' first 100 degree readings of the year this week.  Gusty north winds will occur today and early Sunday with light winds the rest of the week.  There could be some afternoon and evening thunderstorms along and east of the Sierra Cascade Crest late in the week.  

The forecast models are very different in the 7 to 10 day forecast with the GFS breaking the ridge down late next weekend and the European continuing a very strong high pressure area over the west. 

The Old Forecaster

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Wednesday, May 25, 2016

Weather Discussion for Wednesday May 25, 2016

Normal high and low temperatures for May 23-May 30 (high/low)...Redding 85/56, Chico 84/53, Quincy 75/40, Chester 71/38, Susanville 73/41, Grass Valley 73/47, Weaverville 78/42, Mt. Shasta 69/41, Yreka 75/43, Alturas 72/38 

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

It looks like the weather will shift into a more normal late spring pattern.   Today there will be still be afternoon and evening thunderstorms over the higher elevations north and east of the valley.   Temperatures will be a little warmer.  

High pressure is slowly building along the west coast, but Friday through Sunday a couple of low pressure troughs will move over it and into the Pacific Northwest.  The north end of the state will see a few clouds from these but no showers. The rest of the north state will be sunny.  Friday through Sunday temperatures will be normal or a few degrees above and there will be light to moderate north winds. 

Monday through next week high pressure will be along the coast. (see map below).  We will have sunny skies with above normal temperatures and light winds.  

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Monday, May 23, 2016

Weather Discussion for Monday May 23, 2016

Normal high and low temperatures for May 23-May 30 (high/low)...Redding 85/56, Chico 84/53, Quincy 75/40, Chester 71/38, Susanville 73/41, Grass Valley 73/47, Weaverville 78/42, Mt. Shasta 69/41, Yreka 75/43, Alturas 72/38 

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

The low pressure area that brought us a cool wet weekend is slowly moving eastward.   However, there is still enough moisture over Northern California to continue a few showers over the higher elevations today and Monday.   The valley will be partly cloudy to partly sunny with the slight chance of a shower passing over the north end in the afternoon.   Temperatures will be a little warmer but still below normal.  Wednesday through Friday we will be drying and warming.   Temperatures will be rising to normal or slightly above by Thursday and Friday.  

A low pressure area will move by to our north on the weekend. (see map below).  This system will bring a few clouds and maybe a shower to the areas near the Oregon border.  The rest of the north state will be partly to mostly sunny and a little cooler.   Gusty northwest to north winds will occur Saturday afternoon and Sunday.

At this time the latest model runs drop another low pressure area over the north state late next week. 

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Saturday, May 21, 2016

Weather Discussion for Saturday May 21, 2016

Normal high and low temperatures for May 16-May 23 (high/low)...Redding 81/54, Chico 82/51, Quincy 73/38, Chester 69/35, Susanville 71/40, Grass Valley 72/45, Weaverville 77/41, Mt. Shasta 69/41, Yreka 75/41, Alturas 69/36 

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

This update is a little late as I was waiting to see the morning model runs.   The cold low pressure area continues over Northern California.  Today and Sunday Northern California will be partly cloudy to cloudy with showers and a few thunderstorms.  Temperatures will continue 10 to 20 degrees below normal with the snow level 5000 to 6000 feet.  

Late Sunday the main low pressure area will move eastward.   However Monday through the end of next week a large scale low pressure trough will be along the west coast. (see map below).   This will allow a series of weak frontal systems or upper level troughs to move across the north state.  Monday through Friday  the north state will be partly cloudy with a few showers over the higher elevations.  The valley will be partly cloudy to partly sunny with isolated showers possible Monday and Tuesday.  Temperatures will continue below normal. 

There is some indications in the latest model runs that another cold low pressure area will be mover the north state next weekend.

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Wednesday, May 18, 2016

Weather Discussion for Wednesday May 18, 2016

Normal high and low temperatures for May 16-May 23 (high/low)...Redding 81/54, Chico 82/51, Quincy 73/38, Chester 69/35, Susanville 71/40, Grass Valley 72/45, Weaverville 77/41, Mt. Shasta 69/41, Yreka 75/41, Alturas 69/36 

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

Ref question this morning.   The low over Ca is a low level "thermal low" caused by the heating of the valley.  A common feature when interior California heats up.  The thermal low doesn't have clouds but draws cool air through the Delta. 

This morning's satellite picture (below) shows the low pressure area dropping southward along the Canadian coast.  This system will reach Northern California late Thursday and then persist over California and west coast through the weekend (see map below).  Today the north state will be sunny and warmer with temperatures 10 to 15 degrees above normal.  Thursday temperatures will begin to cool and we will see increasing southwest to northwest winds in the afternoon.  There could be isolated showers in the northern mountains by evening.  Friday and Saturday Northern California will have partly cloudy to cloudy skies with scattered showers and thunderstorms.  Temperatures will be 10 to 20 degrees below normal and snow levels will be 5000 to 6000 feet. Gusty southwest to northwest winds will continue through Saturday.

Sunday the low pressure area will begin to move slowly eastward.   The showers should end over the valley but continue over the higher elevations.  Monday and Tuesday a weak low pressure trough will move across our area with a few clouds and showers in the mountains. Temperatures Monday and Tuesday will continue 5 to 10 degrees below normal. 

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Monday, May 16, 2016

Weather Discussion for Monday May 16, 2016

Normal high and low temperatures for May 16-May 23 (high/low)...Redding 81/54, Chico 82/51, Quincy 73/38, Chester 69/35, Susanville 71/40, Grass Valley 72/45, Weaverville 77/41, Mt. Shasta 69/41, Yreka 75/41, Alturas 69/36 

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

I try to answer questions in the comments section as they area posted.   The one I haven't is about the localized layer of warm air.   Bombillo, could you give me a link.  Cliff Mass had post about a layer of warm air but was attributing it to the subsidence from the persistent high pressure ridge that we saw in April.

Sunny and warmer through Wednesday as high pressure is along the coast.   Temperatures by Wednesday will be 10 to 12 degrees above normal.   Gusty north winds will occur today through early Wednesday.

Thursday a cold...for this time of year...low pressure area will be dropping southward along the coast. (Map 1).  This low will remain along the California coast or over Northern California through midday Sunday.  This system will bring cooler and windy weather to the north state.   Thursday afternoon through Saturday we will have partly cloudy to cloudy skies with scattered showers and thunderstorms over the foothills and mountains with isolated activity in the valley.   Snow levels Friday night and Saturday will be 5000 to 6000 feet.  Sunday there will be a few showers over the higher elevations.

The cooler...unsettled...(I hate using unsettled in a forecast)...weather will continue through the early part of next week.   Map 2 below shows a weak low pressure area approaching the coast and this will bring showers to the north state early next week 

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Saturday, May 14, 2016

Weather Discussion for Saturday May 14, 2016

Normal high and low temperatures for May 9-May 16 (high/low)...Redding 81/54, Chico 81/49, Quincy 73/38, Chester 68/35, Susanville 71/40, Grass Valley 71/45, Weaverville 77/40, Mt. Shasta 68/39, Yreka 73/41, Alturas 67/34 

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

Here is a link to the latest El Nino/La Nina discussion http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso_advisory/ensodisc.html
Jan Null of Golden Gate Weather Service has a good discussion here http://ggweather.posthaven.com/ of what this means or doesn't mean for the west.   Not much of a correlation.

A low pressure area is now moving onshore.  Today this system will bring scattered showers and thunderstorms to the higher elevations with isolated activity possible in the north valley.  Sunday there will still be clouds and a few showers east of the Sierra Cascade Crest with sunny skies elsewhere.  Gusty southwest to northwest winds will occur in many areas.  Monday and Tuesday the north state will be sunny with normal or slightly above normal temperatures and gusty north winds. 

Wednesday things start to change the high pressure area weakens as a low pressure area from the Gulf of Alaska begins to drop southward along the coast.  Wednesday temperatures will be cooler and there could be a few showers in the northern mountains late Wednesday.

Thursday through Saturday will be windy and cooler.  The models are in better agreement with the low moving southward along the coast and then over Northern California Friday and Saturday. (see map below).  A slight shift westward in this track would make this a wetter storm.  Thursday through Saturday we will see partly cloudy to cloudy skies with showers and thunderstorms over the higher elevations with isolated activity in the valley.  Temperatures will be below normal with snow levels 5000 to 5500 feet by Friday.   Gusty southwest to northwest winds will occur over most areas.  

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