Tag Archives: west coast

NYC Weekend Weather & West Coast Storm – Dec 2, 2014

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It’s been a up and down week for weather in NYC, with Monday starting out in the mid-60s, then a colder mid-week that featured some mixed precipitation and rain. The end of this week will feature rain and slightly warmer temperatures by Saturday, then a return to colder conditions Sunday into next week. I’m also going to point out some of the spectacular weather brought on by a huge Pacific storm that hit California this week.

Thursday – the remainder of today will be pleasant and sunny, though cold with high temps only in the low 40s.

Friday – clouds will begin to build overnight tonight ahead of the a storm system moving in from the Southern Plains to the Ohio Valley. There is a small chance for scattered showers, otherwise expecting a cloudy day with highs in the mid-40s.

Saturday – rain should overspread the area by Friday night into Saturday. This storm system will be drawing on energy and moisture from the Pacific storm that slammed California earlier this week (discussed below). Combined with influx of Gulf moisture, this setup favors a moderate to at times heavy rain event for Saturday. Temperatures will rise steadily ahead of this storm system as it pushes warm air up. High temperatures Saturday should reach into the mid-50s despite rain and clouds.

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GFS model output for overnight Friday into Saturday

Sunday – rain should end overnight Saturday, and high pressure from Canada should quickly build in behind this storm system. The positioning of this high pressure, along with the exiting low, will make for a tight pressure gradient, which should allow for stiff northwest winds perhaps in the 15-25mph range. Temperatures will drop back into the low 40s with the arrival the colder Canadian air.

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GFS model output for Sunday night

Monday – the storm system from Saturday will move offshore, but it appears from model runs that there’s some chance the storm lingers. As the high pressure from Sunday moves off to the northeast, the clockwise flow behind it may draw this offshore area of low pressure back into the area. This could lead to some rain on Monday. It’ll be a mostly cloudy day otherwise with highs in the low 40s.

Pacific Storm Slams California

Earlier this week, California got slammed by a very strong Pacific low. This storm brought on furious rains that dropped 1″+ in many areas of Northern California, with totals as high as 3-4″ in spots near the Coast Range and Sierra, as well as further south in the mountains east of San Diego. These totals represent more rainfall than had fallen in many of these areas all of last year.

You can see from the map below which overlays drought conditions (the deeper the red, the more extreme the drought, with the darkest red representing extreme/record-breaking drought) with rainfall totals from yesterday. You’ll see that much of the heaviest rain did fall over regions worst affected by drought. Sadly, though this is a case of too much of a good thing, as much of this desperately needed rainfall occurred so quickly, it will simply runoff back into the ocean.

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Map of California with drought condition layer (reds/oranges), and rainfall totals from yesterday

NYC Weather – Spring Climate Outlook – Mar 20, 2014

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Today is the vernal equinox and marks the first day of astronomical spring (because as next week will show, even though it is technically ‘spring’, it won’t feel that way from a weather or climatological perspective).

The equinox denotes the precise date when the sun is directly overhead of the equator at noon. Although it is popularly stated that the equinox is also the date when the length of day and night are equal, this is not necessarily true depending on where you are on the planet. For example, the exact length of daylight for NYC today is 12 hours and 8 minutes, according to astronomical data from Weather Underground. That means the actual equinox for NYC occurred a couple of days ago.

Spring Climate Outlook

This is a good time for us to look ahead towards the forecast climate trends for the United States. Below you’ll see a map showing the Climate Prediction Center’s three-month outlook for both temperature and precipitation. Note that the northern tier of the US is forecast to have anywhere between 33% and 40% chances of a cooler than average spring, while much of the southern and western US is forecast to have between 33% and 50% chances of a warmer than average spring. California in particular is forecast to have 50% chance of warmer than average spring, combined with 33%-40% chance of below normal precipitation, which will be conducive for the persistence of the severe drought in the region.

NYC and the surrounding region is in a zone of equal chances, meaning there’s no strong indication as to whether we’ll have an above, below, or normal spring in terms of both temperature and precipitation.

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NYC Weather Update – Mar 17, 2014

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We were fortunate to avoid a white Monday, as our friends to the south in NJ, DC, and Philadelphia got hit with between 4-9″ of snow during this last storm. Once again, despite temperatures being cold enough, we missed the area with higher moisture content, and dry air took the day, leading to some light flurries but no accumulation.

Check out the snow total map for the DC, Maryland, Delaware, and Southern NJ region below:

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Looking ahead to the rest of the week, it looks like the formal start of Spring will bring a significant warmup for the area.

Tuesday – A sunny day as the departing storm and associated clouds clear out overnight. Good conditions for radiational cooling will mean a cold start to the day with lows in the mid 20s. However, ample sun will boost high temps up to near 40.

Wednesday – the next storm system approaches overnight Tuesday into Wednesday. A low pressure center will pass over the Great Lakes and to our north, with an accompanying trailing cold front. Temps ahead of the cold front will warm up to near normal for this time of year in the upper 40s, near 50. The cold front will bring along light showery precipitation during the afternoon Wednesday. See forecast diagram from the National Weather Service below:

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End of the week will feature high pressure over the area with milder temps near the seasonal average of 50, and fair conditions. The next storm system is forecast to enter the area Friday night into Saturday.

Strong Pacific Storm Possible 10 Days

Parts of the west coast continue to see some abatement of drought conditions, with significant improvement for portions of Oregon and Northern California. Nine of twelve GFS model ensemble members are forecasting a strong Pacific storm coming ashore mid-week next week, which is good news for areas that could definitely use the rain. Below are two of the ensemble members. Note the fairly tight isobars denoting pressure, indicating a strong low pressure center.Screen shot 2014-03-17 at 3.11.55 PM

NYC Weekend Weather Update & CA Storms – Feb 27, 2014

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First up for the NYC area is a bitterly cold end to the work week.

A reinforcing arctic cold front is set to push through the area during the day today, perhaps spurring a few scattered moderate-heavy snow showers. Accumulation, if any, should be light. Behind this frontal boundary, a west wind between 15-20mph will usher in some of the coldest low temps we’ve seen in recent weeks. Lows in the city are forecast to be in the low teens, with zero to single digits in the interior. Wind chill values tomorrow morning will hover around zero.

Friday will be a sunny day with high pressure moving in. Despite the sunshine, temps will struggle into the 20s across the region.

Saturday, a weak frontal system moves through, but with dry atmospheric conditions, little if any snow is expected. Highs will be in the low-mid 30s.

Sunday-Monday, a prolonged winter weather event is forecast. The storm system currently impacting the west coast (see below) will move over the interior of the country, reorganize, and strengthen over the Midwest. This will lead to a stalled cold front draping across our region with multiple low pressure centers to slide along this front. One of these is forecast to develop into a potentially significant coastal storm. Models are coming into agreement that this storm center could pass close to the 40N 70W benchmark sweet spot.

The duration of the storm, starting Sunday night through Monday night means that it could result in significant snowfall, even with possible mixing in with sleet/rain near the coast during the day Monday. Still too early to tell how much snow – will keep monitoring the situation. High temps on Sunday will be in the mid 30s, then drop back into the low 30s for Monday.

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Too much of a good thing for California?

As I noted in earlier posts, and as has been broadcast by the media, California remains in the grips of a crippling drought. A strong pacific storm system is spinning up multiple bands of heavy precipitation during the end of this week. While that is some good news for the drought, the intensity of the rainfall could lead to mudslides, and localized flooding. The best news out of this storm is that elevations over 7000′ are expected to pick up as much as 1-3′ of snow, adding to a paltry snowpack thus far. Check out the graphic from the San Diego NWS station for a look at the heavy rain fall totals expected (5-7″ in higher elevations near the coast with south facing slopes!).

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