Category Archives: Rain

NYC Memorial Day Weekend Weather – May 28, 2021

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Quite a different picture this weekend versus last weekend. Instead of summer like warmth, temperatures will be 10-20ºF below normal in the 50s-60s Saturday and Sunday. A series of slow moving coastal lows is the culprit, bringing much needed rain, and the most substantial rain since the beginning of the month. Memorial Day looks sunnier with temperatures climbing back towards normal in the 70s.

Rest of today – increasing clouds, high temperature in the mid-upper 60s. Rain begins to arrive towards the late afternoon and continues on right through the overnight hours. Overnight lows dropping to around 50ºF.

Weather Prediction Center surface forecast for 8 AM Saturday. A low pressure center moving from the Ohio Valley will elongate with a stationary front extending east-northeast offshore of the region. Waves of low pressure will the move along this boundary this weekend bringing multiple rounds of rain.

Saturday – windy, rainy, and raw, with temperatures only in the mid-50s, which is more typical of March than May. Persistent northeasterly onshore flow with a stationary front positioned south of the region and waves of low pressure moving along it will act to keep things cloudy and cool. Overnight lows again around the 50ºF mark with rain chances backing off but still possible.

Sunday – another low pressure moving along that stationary front will bring more chances for rain particularly early in the day. High temperatures slightly warmer in the low-60s. Overnight lows in the low-50s.

GFS model 1000-500 mb thickness and precipitation type for 11 AM Sunday. Another area of low pressure is depicted impacting the area.

Monday – the unsettled weather finally moves off with a return to sunnier weather. High temperatures Monday should hit the low-70s as a result. Overnight lows in the upper-50s.

NYC Weather Update – May 24, 2021

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Welcome relief from the heat today with high temperatures below normal in the 60s as cool, onshore flow sets up. The warmth returns by mid-week with highs again touching 90ºF by Wednesday. A strong thunderstorm is possible with a cold front passing through that day. Afterwards, temperatures cool but still reach above average highs in the low-80s on Thursday.

Rest of today – partly sunny with gradually increasing sun, high temperatures in the mid-60s with easterly and northeasterly winds shifting towards the southeast. Overnight lows in the mid-50s.

Weather Prediction Center surface analysis for valid 5AM Monday. Overnight, a cold front pushed southwest of the area, allowing for a much cooler air mass to take hold, with easterly onshore flow off the still as yet cold waters of the Atlantic.

Tuesday – warmer with high temperatures in the low-70s and partly sunny skies. Overnight lows in the mid-60s.

Wednesday – a warm front will pass through and put us in the warm sector of a strong low centered well to our north over Canada. Temperatures are expected to reach around the 90ºF in the city. Later in the day, as a cold front approaches, scattered but possibly strong thunderstorms could roll through. Overnight lows in the upper-60s.

GFS 850 mb temperature anomalies for Wednesday at 5PM. We are forecast to see +7ºC anomalies at this level of the atmosphere, corresponding to much above normal temperatures at the surface.

Thursday – skies clear out with high temperatures in the low-80s. Overnight lows around 60ºF.

Subtropical Storm Ana

Over the weekend, the first named storm of the 2021 Atlantic hurricane season, Subtropical Storm Ana, formed over the open waters of the Atlantic northeast of Bermuda. While the storm itself was never a threat to land, it does mark the seventh year in a row that a named storm formed ahead of the formal start of the hurricane season.

GOES satellite imagery showing the circulation of Subtropical Storm Ana

We can’t draw any conclusions from a single storm, but it is worth noting that nearly all major forecast sources including NOAA are calling for a season of above average hurricane activity.

NYC Weekend Weather – May 21, 2021

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A dramatic warm up in store this weekend with highs climbing into the mid-80s and the 90ºF mark. A couple of scattered chances for thunderstorms come with a weak shortwave Saturday and a cold front passing Sunday. This second front will cool things back to seasonable temperatures in the low-70s to start off next week. Yet another warm spell with 90s is taking shape for mid-week next week!

Rest of today – partly cloudy with high temperatures in the mid-upper 70s in the city as high pressure remains dominant, cooler at the coast with a sea breeze developing. Overnight lows in the low-60s.

GFS model 500 mb height and vorticity for Saturday at 8PM. A shortwave with attendant vorticity is visible across Southern New England stretching west-southwest into PA and OH.

Saturday – partly sunny with high temperatures in the mid-80s as a warm front pushes through. A chance for showers and thunderstorms mainly in the interior as a shortwave passes later in the day. Overnight lows quite warm, in the upper-60s, could break records for the warmest minimum temperatures for this day.

Sunday – mostly sunny with high temperatures warming to the 90ºF mark in the city, possibly warmer. Downsloping northwesterly flow should aid this warmup. An isolated shower or thunderstorm is possible later in the day with a weak cold front approaching. Overnight lows dropping to the low-60s.

GFS model 2-meter above ground temperature and 10-meter above ground temperature for 2 PM Sunday.

Monday – big difference in temperatures with high temperatures back in the low-70s behind the cold front passing on Sunday. Overnight lows in the mid-50s.

NYC Weather Update – Apr 26, 2021

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Late April jumps into June with temperatures soaring into the 80s by midweek before a storm system approaches. This could bring us chances for rain on Thursday, while also cooling temps back to normal levels (mid-60s) by the end of the week.

Rest of today – sunny with breezy northwest winds around 20 mph. High temperatures in the low-60s. Overnight lows in mid-40s with winds diminishing as a low pressure center moves off into the Atlantic, relaxing the pressure gradient.

Weather Prediction Center surface forecast for 8AM Tuesday. A warm front will be approaching from the south. Behind this, much warmer air will be flowing clockwise around the high pressure centered off the Southeast coast of the US.

Tuesday – much warmer with high temperatures near 70ºF with sunny skies. Overnight lows in the mid-50s.

Wednesday – we will be firmly within the warm sector of the next approaching storm, and as a result, we should see temperatures rise well into the low-80s (potentially 15-20ºF above normal). This is in part due to an anomalously warm mid-upper level ridge (see below). Clouds will be on the increase as the next frontal boundary approaches. Overnight lows in the low-60s.

GFS 850 mb temperature anomalies for Wednesday at 2PM. We are forecast to see +8ºC anomalies at this level of the atmosphere, corresponding to much above normal temperatures at the surface.

Thursday – the slow moving cold front will start to impact the region with increasing chances for rain. With clouds and rain, temperatures are expected to drop back to the mid-70s. Overnight lows around 60ºF with rain chances continuining.

NYC Weather Update – Apr 19, 2021

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A week of contrasts is in store, starting with warm, above average temps in the 60s and 70s Monday and Tuesday, then rain coming mid-week, caused by a vigorous cold front. Behind this, temperatures will plummet to below normal in the low-50s by Thursday. There are rain chances Monday afternoon with scattered showers and thunderstorms and more substantial chances Wednesday.

Rest of today – starting off sunny, with highs climbing into the mid-60s. Later in the afternoon, clouds develop with a shortwave moving through the area. This mid-level disturbance could see some scattered showers and thunderstorms. Overnight lows in the upper-40s with clearing skies.

HRRR model simulated radar valid for 6 PM this evening. Some scattered showers and thunderstorms are possible especially inland north and west.

Tuesday – best day of the week with high temperatures rising into the low-70s under sunny skies ahead of the incoming storm Wednesday. Overnight lows in the low-50s.

Wednesday – rain chances increasing during the day into the overnight hours. High temperatures in the low-60s under mostly cloudy skies. Behind the frontal boundary bringing the rain, strong cold air advection kicks in, dropping lows into the upper-30s.

Weather Prediction Center surface forecast for 8AM Wednesday. A low pressure center will be progressing through the region bring through a cold front, showers and scattered thunderstorms.

Thursday – sunny in the morning with more clouds developing in the afternoon. With a cold start, high temperatures only hitting the low-50s. Overnight lows dropping to the low-40s.

NYC Weekend Weather – Apr 16, 2021

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A steady warming trend takes place this weekend on the heels of a late season snow storm for interior New England. Temperatures will go from below normal in the low-50s to about average for this time of the year in the low-60s. High pressure brings us decent conditions but rain chances are not out of the question Sunday and Monday with some mid-level disturbances possibly bringing some showers.

Rest of today – wraparound moisture from a late-season Nor’easter that’s bringing accumulating snow to interior New England could bring some showers later today. Otherwise partly sunny with high temperatures on the cool side in the low-50s with northwesterly winds keeping a cap on temps. Overnight lows in the low-40s as rain chances die down.

Weather Prediction Center surface forecast for 8AM Saturday. Low pressure off of New England will be pulling to the east, but still close enough to give us some clouds.

Saturday – partly sunny with high temperatures in the upper-50s. Overnight lows in the upper-40s. Weak high pressure should keep any rain at bay.

Sunday – mostly cloudy, with high temperatures warming into the low-60s. Slight chance for showers in the afternoon. Overnight lows in the mid-40s.

GFS model 500 mb height and vorticity for Monday at 8AM. A fairly potent area of vorticity (dark purples) associated with a shortwave could bring some showers to the area.

Monday – mostly sunny to start with high temperatures in the mid-60s. Rain chances pick up in the afternoon with diurnally driven showers that could get a boost from some mid-level vorticity. Overnight lows at or slightly below 50ºF.

NYC Weather Update – Apr 12, 2021

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We started April off with an extended period of dry, sunny weather featuring several days with well above average warmth. All that changed over the weekend with rain moving in yesterday. These needed rain chances will punctuate this week, tapering off later towards the weekend. Temperatures during this stretch will generally be below normal in the mid-50s to 60ºF with rain and clouds lingering.

Rest of today – cool, cloudy, with showers at times, high temperatures in the low-50s. Overnight lows in the mid-40s with rain chances continuing. This is all due to a relatively stationary surface trough to our south and west.

Weather Prediction Center surface forecast for 8AM Tuesday. During the day, weak high pressure builds allowing for a dry, sunny day.

Tuesday – sunny with high temperatures in the low-60s as high pressure manages to build in briefly. Overnight lows in the upper-40s.

Wednesday – slightly warmer with high temperatures in the low-60s again but mostly cloudy skies. Slight rain chances during the day. Overnight rain chances continue, with lows dropping to the upper-40s.

ECMWF model 500 mb height, and winds for 8AM Thursday. A closed 500 mb low moving over the Great Lakes brings us the next chance for more sustained rain.

Thursday – another rainy day in store as high temperatures drop back to the mid-50s under mostly cloudy skies. A 500 mb closed low moving over the Great Lakes will supply the instability needed to touch off some showers. Overnight lows dropping to the mid-40s.

NYC Weather Update – Mar 29, 2021

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A cool and breezy start to the week with temperatures warming into the 50s and low-60s by midweek. A storm system arrives Wednesday bringing a round of soaking rain. An even colder air mass sweeps in behind this storm with below average highs in the upper-40s. Overnight lows going into Friday may dip into the upper-20s.

Rest of today – breezy with with northwesterly winds 20-25 mph and gusts up to 45 mph. A wind advisory is in effect as a result. Mostly sunny with high temperatures in the mid-50s, but feeling like the mid-40s with the wind chill. Overnight lows in the low-40s.

Weather Prediction Center surface forecast for 8AM Tuesday. High pressure will be more directly overhead and ease winds in the region. Warmer flow from the southwest should help temperatures up into low-60s.

Tuesday – sunny with high temperatures in the low-60s. Much less windy with high pressure more directly overhead. Overnight lows in the mid-40s.

Wednesday – slightly warmer with high temperatures in the low-60s but with mostly cloudy skies. Rain moves in later in the day, and will be moderate and steady. Overnight lows drop considerably to around 40ºF with robust cold air advection behind the cold front bringing this rain.

GFS model 850 mb temperature, height, and winds for 8PM Thursday. Much colder temperatures at this height are forecast. 850 mb temperatures are often a decent proxy for surface temperatures.

Thursday – wraparound moisture with this storm may bring about more showers Thursday morning with high temperatures in the upper-40s. Overnight lows dropping to around 30ºF as skies clear.

NYC Weekend Weather – Jan 15, 2021

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Our extended period of calm weather comes to an abrupt end this weekend. A low pressure system with its attendant vigorous cold front sweeps through overnight bringing moderate to heavy rain. We could see as much as 1-1.5″ of rain with this event. Behind this front, windy conditions prevail Sunday as the low exits but continues to deepen. Next week, we’ll see a return to normal temps around 40ºF.

Rest of today – mostly cloudy with high temperatures in the mid-40s. Rain chances increase as the storm system approaches us. Warm air advection associated with the warm front of this storm will result in little movement on overnight lows, which will hover in the mid-40s. Moderate to heavy rain is likely after 9PM tonight and into the overnight hours.

High Resolution Rapid Refresh simulated radar for 1AM Saturday.

Saturday – as the storm pulls off to the east in the morning, rain chances should decrease, ending by noon. Isolated wrap around showers are possible. Temperatures will decrease during the day with cold air advection, dropping into the low-40s. Overnight lows in the mid-30s as skies clear.

Sunday – mostly sunny with high temperatures in the low-40s. Breezy with west winds in the 15-20 mph range and stronger gusts due to a large pressure gradient around the exiting and intensifying low. Overnight lows in the mid-30s.

Weather Prediction Center surface forecast for 7AM Sunday. The low affecting us this weekend is seen in the upper right corner, with a tight clustering of isobars around it, indicating a large pressure gradient.

Monday – an upper level low will affect the area pushing a cold front through our region, but this front should be moisture starved. Partly sunny with highs around 40ºF. Overnight lows around 30ºF.

NYC Weather Update – Dec 29, 2020

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Messy weather ahead going into the New Years holiday for NYC. We start with high pressure moving overhead. This then gives way to a frontal system tomorrow night. After a brief lull, another storm, similar in some ways to the Christmas storm comes in Friday. Both these precipitation will be rain in the city. Temperatures during this period will generally be above normal in the 40s, warming into the mid-upper 40s.

Rest of today – partly cloudy with high temperatures around 40ºF. Clouds will be streaming in from the northwest, originating from the Great Lakes as lake effect snow showers. These clouds will tend to thin out as northwest flow downslopes dries out across the higher terrain north and west of the city. This northwest flow could also result in some strong wind gusts. With strong high pressure forecast to move nearly directly overhead tonight, winds should calm with skies becoming mostly clear. This will favor good radiational cooling, leading to cold overnight lows in the mid-20s.

GOES Geostationary Satellite visible imagery this morning showing clouds streaming off the surface of the Great Lakes towards the East Coast.

Wednesday – partly cloudy with high temperatures again around 40ºF. Overnight, a warm front passes, followed by a cold front. This will result in an increase in temperatures overnight from the mid-30s as well as rain.

Thursday – a mild day despite the passage of the cold front mentioned above, with forecasters noting the air mass behind the front being of milder Pacific origin. High temperatures around 50ºF. Rain chances should diminish quickly after the morning passage of the cold front. The respite will not last too long as the next storm system follows up quickly. Overnight temperatures dropping into the low-30s.

  • ECMWF “Euro” model 24 hour quantitative precipitation forecast ending 7AM Saturday, about .70″.
  • GFS model 24 hour quantitative precipitation forecast ending 7AM Saturday, close to 1″.

Friday – high temperatures in the mid-40s with another storm system approaching. Rain chances increase going into the overnight hours. This storm, like the Christmas storm, is expected to deliver some moderate to heavy rain. However, since it’s forecast to be weaker overall, the winds and precipitation totals shouldn’t be nearly as robust as the last storm. Overnight should shape up to be similar to Wednesday, where temperatures may actually increase into the upper-40s with the passage of a warm front and corresponding warm air advection.