7:00 AM | Unsettled weather continues into early next week; meteor shower tonight

6-Day Forecast

Today

Mostly cloudy, breezy, showers still likely and maybe a thunderstorm mixed in, cool, highs near 60 degrees

Tonight

Mostly cloudy, maybe a lingering evening shower, very cool late, lows in the mid-to-upper 40’s

Friday

Mainly sunny, breezy, cool, upper 50’s

Friday Night

Mostly cloudy, a shower possible, cool, near 50

Saturday

Partly sunny, cool, maybe a few showers, low 60’s

Sunday

Mostly cloudy, cool, showers possible, near 60

Monday

Mostly sunny, not as cool, mid 60’s

Tuesday

Partly sunny, cool, low 60’s

Discussion

An active pattern will continue into early next week as a series of storms move through southwest California. The first storm in this series will gradually pull out of the region today although lingering showers are possible and there can be a thunderstorm mixed in given the chilly air in the upper atmosphere. More showers are possible from the next system later this weekend.

Video

httpv://youtu.be/2coMVodoeDc

7:00 AM | Decent weather continues today; meteor shower tonight; weak system arrives later tomorrow/tomorrow night

6-Day Forecast

Today

Mostly sunny, cool, highs in the low 50’s

Tonight

Mostly clear, cold, lows in the upper 20’s; METEOR SHOWER

Friday

Mostly cloudy, chilly, a little rain or snow possible late, mid 40’s

Friday Night

Mostly cloudy, cold, maybe a rain or snow shower, mid 20’s

Saturday

Partly sunny, chilly, low 40’s

Sunday

Mostly sunny, cold, near 40

Monday

Mostly sunny, cold, upper 30’s

Tuesday

Mostly sunny, not quite as cold, low-to-mid 40’s

Discussion

Southwest flow will continue around here through tomorrow as an upper level trough approaches the region. That trough should pass through Colorado by later tomorrow and there is the chance for a little rain or snow on Friday; however, this system has rather limited moisture content. Upper level ridging will take place over the weekend with generally dry conditions expected.

Video

httpv://youtu.be/2coMVodoeDc

2:45 PM | Geminid meteor shower peaks pre-dawn Friday

Discussion

The final major meteor shower of the year, Geminid, will peak between 1 and 3am in the pre-dawn hours on Friday, December 14th, and it should be a good show. The annual Geminid meteor shower was first sighted in the early 1800’s with rates of about 20 per hour, but rates have actually increased over the decades to about 100-120 per hour at the peak if skies are clear. There will be no moon around to spoil the show and right now the forecast looks quite favorable albeit cold. The Geminids actually do not appear when a comet’s tail swings by the Earth, but rather when the Earth comes in contact with the particles associated with a rocky object called 3200 Phaethon that may be a chip from an asteroid, but some astronomers are not totally convinced about that theory. Particles that originate from an asteroid would likely be denser and more durable than typical cometary particles that make up other shows, and these would typically survive lower in the atmosphere.

7:00 AM | Pacific storm to bring a soaking rain to the region from later today into tomorrow; snow levels will drop significantly with this storm over the next 12-24 hours

6-Day Forecast

Today

Mostly cloudy, rain develops late in the afternoon, cool, highs in the low 60’s

Tonight

A soaking rain, breezy, cool, lows in the low 50’s

Thursday

Lingering showers likely and maybe a thunderstorm, cool, upper 50’s

Thursday Night

Cloudy, a shower possible early, cool, near 50

Friday

Partly sunny, cool, near 60

Saturday

Partly sunny, cool, low 60’s

Sunday

Mostly cloudy, cool, some rain possible, near 60

Monday

Partly sunny, not as cool, near 65

Discussion

A storm dropping southward along the west coast today will spread rain into the LA metro region by later this afternoon and the steadiest rainfall will occur tonight. Showers will linger tomorrow and as the upper atmosphere cools off, there can be a thunderstorm mixed in. Snow levels will drop during the storm over the next 24 hours to the lowest levels seen so far this season. This cold storm had its origins over the Gulf of Alaska and will pull away from the region on Friday.

Video

httpv://youtu.be/JGV2w3Zta5Q

7:00 AM | Milder today thanks to a southwesterly flow of air ahead of a Pacific Ocean storm

6-Day Forecast

Today

Mostly sunny, breezy, warmer, highs in the low 50’s

Tonight

Mostly clear, cold, lows in the mid-to-upper 20’s

Thursday

Mostly sunny, chilly, upper 40’s

Thursday Night

Partly cloudy, cold, mid-to-upper 20’s

Friday

Partly sunny, still chilly, low-to-mid 40’s

Saturday

Mostly sunny, cold, upper 30’s

Sunday

Mostly sunny, chilly, low 40’s

Monday

Mostly sunny, chilly, low 40’s

Discussion

A deep upper level trough of low pressure will drop southward along the west coast today and this will produce a southwest flow of air over the southern Rockies. Temperatures will respond by climbing to 50 or above along with some sunshine and a gusty southwest breeze. The dry and milder weather will continue on Thursday as well, but it’ll get slightly cooler at the end of the week.

Video

httpv://youtu.be/JGV2w3Zta5Q

11:20 AM | Interesting atmospheric and oceanic signals around the world may foretell a pattern change in the Northeast US to colder and stormier as we progress through the second half of December

Discussion

Some very interesting atmospheric and oceanic events around the world may very well be signaling a change to the overall weather pattern here in the northeastern US as we progress through the second half of the month to one that is stormier and colder. The northeastern US has largely avoided any sustained cold weather during the month of December and accumulating snow has been quite sparse. At the same time, several regions around the world have suffered through some serious cold spells with snow including in much of Europe, Asia, western Canada and Alaska.

To begin with, there has been a sudden warming of stratospheric temperatures in the northern latitudes in recent days. This sudden change in the upper atmosphere followed several weeks of orderly temperature drops. Secondly, a daily index that is tied to the tropical Pacific Ocean sea surface temperature pattern called the Southern Oscillation Index (SOI) has plunged in recent days deep into negative territory following several weeks of slightly positive readings. If sustained, negative SOI readings can indicate some warming of sea surface temperatures in tropical Pacific waters which can, in turn, help to activate the southern jet stream across the US. Finally, another index that we closely monitor here during the winter season is the North Atlantic Oscillation (NAO), and it has dropped sharply in recent days into negative territory. A sustained negative NAO can be a leading indicator to a stormier and colder pattern in the northeastern US depending on some other factors. Some of the computer forecast models are now picking up on a stormier pattern in coming weeks for the northeastern US; however, it is likely that the models will have all kinds of difficulty and variability during this pattern transition period - and we’ll continue to monitor it at thesiweather.com.

Video

httpv://youtu.be/WVm_vEZcrf0

7:00 AM | Storm threatens us with soaking rain later tomorrow into Thursday; snow levels will drop during the storm to the lowest levels of the year so far

6-Day Forecast

Today

Clouds early then some sunshine, pleasant, upper 60’s

Tonight

Mostly clear early, clouds late, cool, lows in the low 50’s

Wednesday

Mostly cloudy, rain develops late in the day, cool, low 60’s

Wednesday Night

A soaking, steady rain, breezy, cool, low 50’s

Thursday

Lingering showers likely and maybe even a thunderstorm, even cooler, upper 50's

Friday

Mostly sunny, cool, upper 50’s

Saturday

Partly sunny, cool, near 60

Sunday

Partly sunny, cool, near 60

Discussion

A big change will take place by later tomorrow across California as a cold storm system approaches the coastline dropping southeastward from the northeastern Pacific Ocean. This storm had its origins over the Gulf of Alaska and it will bring periods of rain to the region from later Wednesday into Thursday along with cooler temperatures. Snow levels will drop during the storm to the lowest levels of the year so far this season. The steadiest, heaviest rain for the LA metro region from this storm appears to be headed our way for the Wednesday night time frame.

Video

httpv://youtu.be/BJKO1lNQv7M

7:00 AM | Moderation in temperatures after bitter cold start to the day

6-Day Forecast

Today

Mostly sunny, very cold start and then moderation in temperatures this afternoon with highs approaching 40 degrees

Tonight

Mostly clear, very cold, lows near 20 degrees

Wednesday

Mostly sunny, not as chilly, low 50's

Wednesday Night

Partly cloudy, cold, mid-to-upper 20’s

Thursday

Mostly sunny, still chilly, upper 40’s

Friday

Partly sunny, cold, low 40’s

Saturday

Partly sunny, cold, near 40

Sunday

Mostly sunny, cold, near 40

Discussion

Temperatures will moderate this afternoon after a very cold start to the day and will remain at moderate levels for the rest of the week. High pressure ridge will generate a strong northwesterly flow aloft today and this will gradually shift eastward during the middle of the week. By late in the week, another storm system will approach the region from the southwest, but its moisture content appears to be rather limited.

Video

httpv://youtu.be/BJKO1lNQv7M

7:00 AM | Brutal start to the new work week, but moderation in temperatures will soon take place

6-Day Forecast

Today

Partly sunny, very cold start to the day, windy, highs later this afternoon in the mid 30’s

Tonight

Mostly cloudy, very cold, lows in the upper teens

Tuesday

Mostly sunny, cold, upper 30’s

Tuesday Night

Mostly clear, very cold, mid-to-upper teens

Wednesday

Mostly sunny, not as cold, near 50

Thursday

Mostly sunny, cold, mid-to-upper 40’s

Friday

Partly sunny, cold, maybe a few snow showers, upper 30’s

Saturday

Mostly sunny, cold, near 40

Discussion

Brutal cold weather will start the new work week, but temperatures will moderate somewhat to near normal this week as high pressure ridge shifts to the east from the western US. Another storm will approach the region late this week and there will be a slight chance for snow showers at that time.

Video

httpv://youtu.be/Dl1SkswjCmU

7:00 AM | Mild through Tuesday, but a chilly storm will move into the region on Wednesday

6-Day Forecast

Today

Morning low clouds and fog then becoming mostly sunny, pleasant, upper 60’s

Tonight

Mostly clear, cool, lows in the low 50’s

Tuesday

Mostly sunny, pleasant, upper 60’s

Tuesday Night

Partly cloudy, cool, low 50’s

Wednesday

Mostly cloudy, cooler, rain likely, low 60’s

Thursday

Mostly cloudy, even cooler, more showers possible, upper 50’s

Friday

Mostly sunny, cool, near 60

Saturday

Mostly sunny, cool, near 60

Discussion

Santa Ana winds will bring warmer temperatures to the region to start the new work week and that will persist into tomorrow. By the middle of the week, a big change will take place which will bring about cooler temperatures and the good chance for periods of rain as a storm drops southward over the next couple of days from the Gulf of Alaska towards the California coastline.

Video

httpv://youtu.be/Dl1SkswjCmU