Category Archives: Outside of NYC

NYC Weather Update – Mar 27, 2014

March 27, 2014Climate, Northwest, NYC, Outside of NYC, Snow, Storms, Weather Update, Weekend, Western USgfs, landslide, mudslide, navgem, nyc, oso, qpf, storms, weatherLei Zhao

We’re entering into a pattern of active weather through the weekend and into early next week. Today will be dry and pleasant, though well below normal with highs only in the mid 40s.

High pressure will move east of NYC before a cold front approaches from our west on Friday. Southwest flow around the high pressure center and ahead of the frontal boundary will usher in milder, moist air from the southeast. Temperatures on Friday will be near normal in the mid 50s. As the front passes through, expect periodic rain showers throughout the afternoon hours.

Saturday – a second frontal system is forecast to spawn a low that will track offshore of the East Coast, bringing a second round of rain to the area. This round will be heavier than Friday’s, with ample moisture available for the storm to draw on. With the clouds and rain, high temperatures will be suppressed to around 50.

Sunday – there is some uncertainty about how quickly the low impacting us Saturday will exit the region. At this time, it does appear that rain will continue through portions of the day. Should the low be slow to exit, colder air could work into the system allowing for accumulating snow Sunday night! High temperatures Sunday will be in the mid 40s.

Monday – should be a fair day, dry, with high temperatures near normal in the mid 50s. So, even if it snows on Sunday, the snow will melt rapidly. Next shot at precipitation comes with another frontal system Tuesday.

Check out the cumulative quantitative precipitation forecast from the National Weather Service’s Weather Prediction Center for Thursday through Sunday morning. Note that our area is forecast to receive as much as 2.5″ of precipitation through Sunday. Also, there are pockets of as much as 4-6″ of precipitation forecast for the West Coast. For California, that’s some good news as it will help with the drought conditions, but as we saw with Oso, Washington mudslide this much precipitation in such a short span of time can lead to landslides. This is especially the case for Oregon and Washington which are no longer as drought-stricken and soil saturated from previous storms.

Below is a NAVGEM forecast model run depicting two storms simultaneously impacting the West Coast and the Northeast on Sunday.

Really Cool Graphic – Frozen Great Lakes

March 21, 2014Cool Images, Outside of NYCcool, erie, great lakes, huron, ice, michigan, ontario, satellite, science, superior, winterLei Zhao

It may be spring now, but it certainly doesn’t look or feel that way for the Great Lakes, most of which are still ice-bound. Superior, Huron, and Erie are still almost entirely covered by ice, while Michigan is less than half covered. The only lake not ice-bound this winter has been Ontario at the far-right. Image from LANCE MODIS taken on March 16th.

You may be wondering why Lake Ontario is the exception to the frosty rule here. Ontario’s average depth is about 283 feet, only Superior has a greater average depth (Erie is the shallowest, so even though it’s further south than Ontario, it’s often the first to freeze). Furthermore, Ontario is located at a lower latitude than Superior and Huron, and it’s relatively smaller surface area maximizes its heat retention.

NYC Weather – Spring Climate Outlook – Mar 20, 2014

March 20, 2014Climate, Noreaster, NYC, Outside of NYC, Western UScalifornia, climate, drought, equinox, nyc, spring, west coastLei Zhao

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.

NYC Weather Update – Mar 17, 2014

March 17, 2014Climate, Drought, Northwest, NYC, Outside of NYC, Snow, Storms, Weather Update, Western UScalifornia, drought, nyc, oregon, snow, spring, storms, weather, west coastLei Zhao

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:

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:

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.

Really Cool Graphic – All Reports of Severe Hail from 1950-2013

March 17, 2014Climate, Outside of NYC, Severe Weather, Thunderstorms, Western UScool, data visualization, gis, hail, history, severe weather, weatherLei Zhao

Another neat graphic from Storm Prediction Center’s SVRGIS: all reports of severe hail over .25″ in diameter from 1950-2013! Again, note the relative scarcity of severe hail west of the Rockies, but look at the density of hail reports over Mississippi and Georgia. Also, check out the dense patch of hail reports just east of the Front Range in Colorado.

Weather Update – Midweek Storm, Mar 11, 2014

March 11, 2014NYC, Outside of NYC, Snow, Thunderstorms, Weather Updatemarch, nyc, rain, severe, snow, storm, thunderstorm, winter, wxLei Zhao

Wednesday is shaping up to be a stormy, rainy day. Low pressure center currently located over Nebraska and Oklahoma will slide to the northeast into the Ohio valley while continuing to strengthen.

Current forecasts point to the storm center tracking just north of the NYC area. This should ensure that most of the region receives all rain for this storm. As the storm center draws closer, a nearly stationary frontal boundary will slowly push through to just north of the NYC area. This will allow the area to be entrenched in the warm sector, this means temperatures will stay relatively mild with highs in the mid-50s. It also raises the possibility for some weak thunderstorms in the afternoon hours as the cold front trailing the storm center pushes through.

In fact, the Storm Prediction Center has placed the DC-PHL metro areas as well as parts of southern Pennsylvania, northern Virginia, Maryland (see diagram below) under a slight risk for severe thunderstorms. The same cold front could trigger stronger storms down to the south due to the likelihood of warmer temperatures, more unstable air, and favorable conditions for thunderstorm initiation.

Behind the cold front, temperatures will plummet during the evening and overnight hours. The departing low will continue to strengthen into Thursday, with increasing northwest winds ushering in this colder air as well as a chance for snow showers (negligible accumulation expected). Highs will only barely hit the mid-20s.

Conditions will improve later in Thursday and Friday as an area of high pressure moves over the region. Temps will climb back into the low 40s Friday just below average, and rise to near 50 Saturday. Next chance of significant precipitation looks to be Sunday into Sunday night – with the potential for a snow storm!

NYC Weather Update – Mar 10, 2014

March 10, 2014NYC, Outside of NYC, Storms, Weather Updatenyc, rain, snow, weather, weather update, winterLei Zhao

After a quiet weather weekend, the NYC area will be experiencing a mid-week storm.

Tuesday – a mild day with partly sunny skies and highs in the mid-upper 50s across the area ahead of the frontal system that will impact the region on Wednesday. The cold front will be draping west-east and positioned through Pennsylvania, allowing a westerly flow of warm air into the area.

Wednesday – the surface low pressure responsible for the mid-week storm will be over the central Ohio valley. Precipitation will extend eastward from the low pressure center along the frontal boundary referenced above. The center of the storm is forecast to pass right over the NYC region. Coastal areas should see all rain from this storm with a warming onshore flow developing (east winds). Areas in the interior could see a mix of rain/snow and possibly freezing rain. Heavy rain could develop during the afternoon hours.

Thursday – the low pressure center will strengthen as it passes over NYC and eventually pushes offshore. Cold air will wrap around the low pressure center and winds will shift to the north and northwest. There’s a possibility that the city could see a transition from rain to snow during this period of cooling temps. Temps on Thursday will struggle to only reach the low 30s.

Friday – high pressure will build in briefly Friday allowing a return to mostly clear conditions and warmer temps in the low 40s before the next storm system moves in with a clipper type system moving in from Canada. Dry conditions should lower chances for precipitation on Saturday.

Below: NAVGEM forecast map for 7PM EST Wednesday night. Notice an area of surface low pressure forming off the coast of Southeast NJ.

NYC Weather Update, Monday Storm – Mar 1, 2014

March 1, 2014Drought, NYC, Outside of NYC, Snow, Storms, Weather Update, Weekend, Western UScalifornia, drought, flooding, mudslide, nyc, snow, weather, winterLei Zhao

Summary

March is coming in like a lion this year (let’s hope it leaves like a lamb), with yet another snow storm to add to our misery here in the NYC area Sunday night into Monday night.

Background

A strong coastal storm that’s currently pummeling California with heavy rain and snow will be transferring its energy and moisture to the aforementioned storm. For California, the rain and snow is a mixed blessing: with a hundred-year drought gripping the region, moisture is welcome; however, so much rain in such a short time window is leading to flash flooding, mudslides, and other headaches. See the video below:

Forecast

Our local NWS forecast office has issued a winter storm watch for Long Island, NYC, and central NJ on south. The latest snow maker will be two waves of low pressure that will travel along the length of an arctic cold front Sunday and Monday. This cold front will across our area during this period, ensuring that the air will be cold enough for all snow during the strongest part of the storm, although precipitation may start off as a rain/snow mix during the day Sunday with highs expected to be in the mid 30s.

The forecast graphic below depicts probabilities of snowfall accumulations at least 6″ or more across the region from 8PM Sunday through 8PM Monday. As you can see, we are right on the cusp of a high confidence zone for more than 6″. As it stands, 6″ seems to be the going number for the areas under the winter storm watch. A slight northward adjustment of the storm track would increase the chances we get more than 8″.

This will be a prolonged weather event – so, moderate snow for a longer time, but less of the heavy snow that we saw with the last storm.

Overnight lows on Sunday will be around 20 in the city, and highs Monday will be in the mid 20s, with the cold air flowing in behind the cold front.

Extended Forecast

Things settle down after the storm passes Monday, with mostly clear and dry conditions Tuesday through Thursday. High pressure will dominate, bringing these clear conditions, but also extending the cold snap well into next week as it continues to pump Canadian air into the area. Highs will continue struggling to reach the mid-upper 20s, with overnight lows in the teens at the coast and single digits in the interior.

Interesting note: some of the GFS (Global Forecast System) models are showing the potential development of a strong coastal storm next weekend. Of course, it’s far too early to talk specifics about precipitation type and amounts as this storm may not materialize. The models are fairly consistent in developing a low over the northern Gulf of Mexico, however, a frontal system also develop to be strong enough to push this storm well offshore as it approaches the region.

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

February 27, 2014Climate, Drought, NYC, Outside of NYC, Snow, Storms, Weather Update, Weekend, Western UScalifornia, cold, nyc, pacific, snow, storms, weather, west coast, wind chillLei Zhao

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.

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!).

NYC Weather, Relief for CA, A Stormy Monday for NY? – Feb 25, 2014

February 25, 2014Climate, Drought, NYC, Outside of NYC, Snow, Storms, Thunderstorms, Weather Update, Western UScalifornia, drought, northeast, nyc, nycwx, pacific, rain, snow, thunderstorms, weather, western us, wxLei Zhao

Keeping eyes peeled on the forecast for Monday, when the next strong storm system is forecast to arrive.

First, there’s some good news for our friends out west. As you can see in this first image, the GFS model is showing a storm system originating in the Pacific bringing areas of moderate to heavy rain over the weekend for California, which is currently in the grips of an historic drought. As the storm center approaches the coast, a strong cold front will swing from south to north through the state. This frontal boundary will spark thunderstorm and rain which should bring mild relief, with 1-2″ of rain forecast for coastal and valley areas, and 2-4″ up to 6″ for south-facing mountain slopes. In addition, heavy snow could fall in the higher elevations of the coastal ranges and Sierra. Welcome news for an area of the country that’s in need of moisture.

After the storm exits the western US, it is forecast to reorganize over the plains and Midwest, then track into our area. Right now, it’s still to early to say with certainty whether the intensity of the precipitation this storm brings, and whether it will be all snow, a mix, or even mostly rain. Will keep you all updated.

LZ | Weather

Weather updates & posts for NYC region