Tag Archives: low pressure

NYC Weather Update – Nov 5, 2019

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The week after we set our clocks back for the fall will see a shift to the coldest temperatures we’ve yet seen this season. High temperatures will trend from normal levels to slightly below normal (upper-50s to low-50s) before plummeting into the 40s following the passage of a low pressure center and cold front. The chilly air following this system will begin a longer term trend of below average temperatures going into the middle of the month at least.

Rest of today – mostly cloudy with a chance of showers as a cold front passes through later in the day. High temperatures on the mild side in the low-60s as we’ll be in the warm sector of the parent low bringing the cold front through. Overnight lows in the low-40s.

Weather Prediction center surface forecast for 7AM Wednesday

Wednesday – sunny with cooler high temperatures in the low-50s. High pressure depicted above will keep things nice and dry. Overnight lows in the low-40s.

Thursday – starting off mostly sunny with high temperatures in the mid-50s. A storm system will approach later in the day and bring the chance for rain at first, with rain and snow mixing possible overnight as lows drop into the mid-30s.

  • Climate Prediction Center temperature anomaly forecast for November 10-14
  • An anomalously low area of 500 mb heights will produce cold temperatures at the surface

Friday – the real cold sets in with high temperatures only in the low-40s. Rain/snow should taper off early giving way to sunny conditions, with winds picking up due to the low bringing this weather strengthening as it continues moving off to the northeast. Overnight lows are shaping up to be below freezing, near 30°F with winds forecast to die down and skies clearing allowing for some good radiational cooling.

NYC Weekend Weather – Oct 25, 2019

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This weekend starts off with fair and dry weather. A storm developing along the Gulf Coast of Texas, tracking north along the Mississippi and Ohio Valleys into the Great Lakes, then east towards our area will bring a prolonged period of steady rain on Sunday. As of 11AM today, National Hurricane Center has designated this storm as Tropical Depression Seventeen. This storm should pull out of the area before the start of next week. Temperatures during this period should be at or above average for this time of the year in the low-mid 60s.

Rest of today – partly sunny to mostly cloudy with a cold front weakening, then stalling and returning north as a warm front. High temperatures in the mid-60s. Overnight lows in the low-50s with decreasing clouds as high pressure builds in.

Weather Prediction Center surface forecast for 8AM Saturday

Saturday – high pressure builds briefly and should give us mostly sunny skies with high temperatures in the mid-60s. Overnight lows in the low-50s with increasing clouds and chances for rain.

Sunday – much like last weekend, a storm with tropical origins will bring rain and lots of moisture to the area. The extratropical remnants of Tropical Depression Seventeen will track north towards the Great Lakes during this period. A warm front attached to it will bring a shield of steady stratiform rain over the area. Mostly cloudy with highs in the upper-60s as winds turn to the south. Steady rain continuing into the early overnight hours until the storm’s trailing cold front finally sweeps through and drier air works in. Lows in the mid-50s.

  • NAM model output for relative humidity and wind at 850 mb for 5PM Sunday. Note the nearly saturated nature of the lower levels of the atmosphere.
  • NAM model output for wind at 850 mb for 5PM Sunday. Note the high wind speeds at this level, indicating the presence of an 850 mb low-level jet (LLJ)
  • NAM model output for precipitable water at 2PM Sunday. Note the high values above 1.50″. This makes sense, given the tropical origins of the storm that will impact us Sunday.
  • Projected track of Tropical Depression Seventeen

Monday – high pressure and calmer conditions return with highs in the mid-60s and mostly sunny skies. Overnight lows in the mid-50s with mostly cloudy skies.

NYC Weather Update – Oct 21, 2019

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Sunny and seasonable weather with highs in the mid-60s will be punctuated by the passage of a strong frontal system mid-week. The timing of this frontal passage should bring the bulk of the rain through overnight Tuesday, such that Wednesday ends up still being a nice day. Looking ahead, a second cold front is forecast to move through late in the weekend but is not expected to bring significant rain at this time. Temperatures throughout this forecast period and beyond are looking to be at or above normal in the low-60s/

Rest of today – mostly sunny, with highs in the mid-60s. Overnight lows in the low-50s.

Weather Prediction Center surface forecast for 8PM tonight. We will be wedged between the storm that brought steady rain yesterday to the east and an approaching frontal system with a parent low over the Upper Midwest.

Tuesday – increasing clouds with high temperatures in the low-60s. Rain chances increasing especially later in the day. Bulk of the rain accompanying the cold front should arrive overnight. Overnight lows in the mid-50s.

Wednesday – rain should clear the area. Temperatures expected to rebound back into the mid-60s under sunny skies with some downsloping westerly flow behind the front. Overnight lows in the upper-40s with a cooler, drier airmass working in.

Climate Prediction Center temperature outlook for Oct 26-30. We will be in an area with about equal chances of above or below normal temperatures up to 33% for warmer than normal temperatures.

Thursday – another really nice day with high temperatures in the mid-60s and mostly sunny skies. Overnight lows around 50°F.

NYC Weekend Weather – Oct 18, 2019

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Soaking rains from Wednesday’s nor’easter have long since exited east, yet we will continue to feel the impact of this low with windy conditions to start the weekend. As the low continues moving east, an area of high pressure will build in and take its place. Winds will relax and we should enjoy a nice, sunny day for Saturday. Clouds are expected to build back in as a potential extratropical remnant low of what could become Subtropical Storm Nestor this weekend pass south of the region. Temperatures during this period are expected to be at or just below normal in the low-60s with a warm up going into next week.

Rest of today – windy conditions continue as the pressure gradient between a building area of high pressure to the west and the low that brought us rain Wednesday which is now over the Canadian Maritimes. High temperatures around 60°F with partly cloudy skies. Overnight lows expected to be quite cool, in the low-40s with skies looking to clear up and winds dying down – conditions that could lead to some strong radiational cooling.

Weather Prediction Center surface forecast for 8AM Saturday

Saturday – high pressure builds in and gives us a sparkling, sunny, fall day with high temperatures in the low-60s. Overnight lows milder around 50°F.

Sunday – although the extratropical remnants of what could be Subtropical Storm Nestor are forecast to pass well south of the area, this storm is expected to have a broad cloud shield to its north, and some outlying rain bands could even result in a couple scattered rain showers for the area. High temperatures should be similar to Saturday in the low-60s, because even with clouds, overall flow will be from the south. Overnight lows around 50°F again.

  • GOES satellite imagery of Potential Tropical Cyclone Sixteen
  • National Hurricane Center’s latest forecast track guidance for this storm

Monday – with this low exiting east, we’ll see more southerly flow ahead of the next incoming storm system. High temperatures should respond by warmingin into the upper-60s with mostly sunny skies. Overnight lows in the mid-50s with mostly cloudy skies.

NYC Weather Update – Oct 14, 2019

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The week starts off with warm temperatures for this time of year, followed by entry of a cooler airmass. A storm system is forecast to bring rain mid-week. Temperatures will cool even more behind this storm with high temperatures dropping to slightly below normal levels in the low-60s by the end of the week.

Rest of today – mostly sunny, with highs in the low-70s. Overnight lows in the low-50s.

Weather Prediction Center surface forecast for 8PM Tuesday

Tuesday – a dry cold front passes over the region later today, leading to cooler high temperatures in the low-60s for Tuesday on the back of colder northwest winds behind the front. It should be a sunny day. Overnight lows in the low-50s.

Wednesday – a low pressure system over the Great Lakes will track east towards the area. Mostly cloudy skies will prevail with highs warming into the mid-60s due to a shift in winds to the south and southeast. Rain should start to overspread the area later in the afternoon and continue overnight. Overnight lows in the low-50s and even cooler possibly in the upper-40s. A secondary coastal low forming off the Carolina coast will become the primary low as energy transfers from the inland storm.

  • GFS model output for 1000-500 mb thickness and precipitation valid 2PM Wednesday
  • GFS model output of the same metrics for 2AM Thursday

Thursday – rain should clear out before the start of the day but winds will be breezy from the northwest. This will bring in cooler air again with high temperatures in the upper-50s and partly sunny skies. Overnight lows around 50°F.

NYC Weekend Weather – Oct 11, 2019

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The persistent storm off the Northeast US coast finally starts to move east. This storm has defied the odds, increasing in organization and intensity overnight, and has just been named Subtropical Storm Melissa. We will enjoy a spell of warming temperatures (from the low-60s into the low-70s) and dry weather leading into early next week as the region sits between the exiting storm and another strong low over the interior of North America. A couple of frontal boundaries will pass over, however, these will be starved of meaningful moisture and should not result in any rain.

Rest of today – mostly cloudy with high temperatures in the low-60s. Overnight lows in the low-50s as winds start to shift to the north due to Subtropical Storm Melissa continuing to move to the east.

Satellite imagery of the incipient Subtropical Storm Melissa

Saturday – mostly cloudy with high temperatures warming to around 70°F. Winds will diminish as Subtropical Storm Melissa finally starts moving east. Overnight lows in the low-50s.

NAM model output for 500 mb heights and wind at 2PM Saturday. A significant closed upper-low, largely cut off from westerly steering currents, will be over the Upper Midwest. A slow-moving, strong occluded low will accompany this upper low at the surface. East of this, there will be some slight ridging, keeping our weather fair.

Sunday – a weakening cold front moves through, but with lack of appreciable moisture, there shouldn’t be any rain. High temperatures will be similar to Saturday, around 70°F, with m ore sunshine expected. Overnight lows in the mid-60s.

Weather Prediction Center surface forecast for 8AM Sunday

Monday (Columbus Day) – the cold front that moves through overnight into Sunday is expected to stall and become stationary. A surface low is forecast to form and move along this boundary near the coast, leading to increasing clouds with high temperatures in the low-70s. Overnight with lows dropping into the upper-50s.

NYC Weather Update – Oct 8, 2019

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A distinct fall feel this week with grey skies the norm and spotty rain chances for many of the days. A coastal storm brewing off the Southeast coast is forecast to track north and then northeast. National Hurricane Center is tracking this system as it has some potential to acquire subtropical characteristics. This will be a slow moving storm that will bring a long period of northeasterly winds to the area.

Rest of today – mostly cloudy, with highs in the upper-60s. Overnight lows in the upper-50s.

  • Weather Prediction Center surface forecast for 8PM Wednesday
  • The developing coastal storm depicted above.

Showers and thunderstorms over the western Atlantic between the southeastern coast of the United States and Bermuda are associated with a broad, non-tropical area of low pressure. This system is forecast to move northward or northeastward and could acquire some subtropical characteristics off the east coast of the United States by the end of the week.

National Hurricane Center

Wednesday – although the storm referenced is forecast to remain well offshore, outer rain bands from it could bring showers to the area along with persistent northeast winds. These wind are anticipated to be on the strong side, steadily in the mid-teens with gusts in the 25 mph range. Mostly cloudy with highs around 60°F. Overnight lows in the low-50s.

Thursday – rain chances continue as the storm develops and becomes a closed low. Mostly cloudy with highs in the low-60s. Winds will become blustery from the northeast around 15 mph with higher gusts. This will be due to the increasing pressure gradient between the deepening low and high pressure over eastern Quebec. Overnight lows in the low-50s.

GFS model output of 850 mb winds and relative humidity. The coastal storm continues to spin off the Northeast coast, although its center remains well offshore (just above the pivotalweather logo in this frame).

Friday – rain still lingers though the storm starts to finally make some eastward progress as a trough approaches from the west. High temperature remain in the low-60s with mostly cloudy skies. Overnight lows in the upper-50s as warmer southerly flow starts to work into the region.

NYC Weekend Weather – Oct 4, 2019

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Strong high pressure and sunny weather will be the main theme this weekend. Despite the sun, we do have a chance to see the coldest overnight temperatures so far this season tonight into Saturday. High temperatures start to warm from the 60s to the low-70s by the second half of the weekend and to start next week as the high pressure progresses east and we get warmer southerly return flow before the next storm system approaches Monday.

Rest of today – sunny with high temperatures in the mid-60s. Breezy with a refreshing northerly wind, 15-20 mph with higher gusts due to the relatively tight pressure gradient between the high pressure building moving in from the west and the low that brought us rain yesterday continuing to move offshore. Cold overnight, with lows in the upper-40s. Frost advisories and freeze warnings are up for many areas of upstate New York not too far from us.

850 mb winds as indicated by GFS model for 8AM today, indicating the presence of strong winds of 30-40 knots just above the surface.
As the day progresses, the near-surface layer up to 850 mb is forecast to become well-mixed, and this will allow the faster winds above to reach the surface.

Saturday – a sparkling, sunny fall day with high temperatures in the low-60s. Wins will calm also. Overnight lows in the mid-50s with increasing clouds.

Weather Prediction Center surface forecast for 8AM Sunday

Sunday – the cloud shield preceding an incoming storm system will continue moving in Sunday resulting in partly sunny skies. High temperatures will warm to around 70°F as winds turn to the south. This is due to the high pressure exiting east (clockwise flow around this) as well as winds ahead of an approaching cold front. Overnight lows in the low-60s.

Monday – mostly cloudy with chances for rain increasing later in the day. High temperatures in the mid-70s. Heavier rain accompanying the passage of a cold front overnight with lows dropping into the upper-50s.

NYC Weather Update – Oct 1, 2019

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This week will see a wild temperature swing that will take us into the upper-80s, giving us a last taste of summer, followed up by a plunge into decidedly fall-like temperatures barely in the upper-60s. Friday night in particular looks like it could be the coldest yet this season, with overnight lows possibly dipping below 50°F. Temperatures start to recover over the weekend to around normal for this time of year around 70°F.

Rest of today – partly sunny with high temperatures warming into the upper-70s, near 80°F. A warm front is forecast to push through and winds will be coming from the southwest, ushering in some renewed warmth. Overnight lows around 70°F.

Weather Prediction Center surface forecast for 8AM Wednesday

Wednesday – with a warm front passing Tuesday, and high pressure setting up over the Southeast US, warm air will be surging from the southwest towards the region. This should allow high temperatures to rise well into the upper-80s and possibly close to 90°F. A cold front will be approaching from the north Wednesday night, bringing along rain and thunderstorms. Temperatures will cool off quickly with the rain and the cold front, dropping into the upper-50s.

Thursday – much cooler with high temperatures only reaching into the low-60s. Rain chances linger during the day with the cold front stalling out south of us and another low pressure center pushing east. Overnight lows not much cooler than daytime highs, around 60°F as rain chances continue.

GFS model output for precipitation, 1000-500 mb thickness, valid for 10AM Friday. Note the relatively closely packed black lines (isobars) between the high pressure centered over Wisconsin and the Low off the coast of Nova Scotia. This pressure gradient will deliver some windy conditions Friday.

Friday – conditions should clear up as the low pressure responsible for rain on Thursday moves off to the east. A tight pressure gradient is forecast to form between this low and a high pressure center building over the Great Lakes. This should result in a windy day, with high temperatures bouncing back into the mid-60s. Overnight lows are forecast to drop to around 50°F with the influence of the much cooler continental polar airmass and north/northwesterly winds.

NYC Weather Update – Jun 17, 2019

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A slow-moving/stalled frontal boundary lingering across the Ohio Valley into the Northeast will bring multiple rounds of rain and thunderstorms. As multiple waves of low pressure travel along this boundary, we’ll see several rounds of rain spread across multiple days, pretty much until the end of the week. During this stretch, because of the cloud cover and rain, temperatures will range slightly below average in the upper-70s.

Rest of today – mostly cloudy with rain arriving later in the day. HRRR (high resolution rapid refresh) simulated radar suggests the onset time of the first round of rain sometime between 5-7PM. This first round of rain isn’t expected to last too long. Overnight, around 1AM, we could see more substantial rain. Temperatures during the day peaking in the upper-70s and overnight lows in the mid-60s.

  • High resolution rapid refresh simulated radar for 5:30PM
  • High resolution rapid refresh simulated radar for 1AM Tuesday

Tuesday – high temperatures in the mid-70s with mostly cloudy skies again. Rain chances more likely in the morning. Overnight lows in the mid-60s.

Wednesday – chance for showers and thunderstorms continues, with high temperatures in the mid-70s and overnight lows in the mid-60s.

Weather Prediction Center surface forecast for 8AM Wednesday

Thursday – yet more chances for rain and cloudy skies with high temperatures in the mid-70s, and overnight lows again in the mid-60s.