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NYC (KLGA) Climatology for November

November 7, 2019Climate, NYCclimatology, cold front, high pressure, new york city climate, new york city weather, new york city wx, nyc climate, nyc weather, nyc wx, warm front, wind roseLei Zhao

During my time taking classes as part of Penn State University’s Undergraduate Certificate in Weather Forecasting, we were taught that understanding the climatology of the location you are interested in is an important prerequisite for making accurate forecasts. This post continues on this theme, adding a climatology for November.

Other Month’s Climatologies

January
February
March
April
May
June
July
August
September
October
December

Station Basic Information

City Name / Station ID: New York, NY (LaGuardia Airport – KLGA)

Local Geography and Topography

Station Elevation: 10 feet above sea level.

Station Location: LaGuardia Airport (KLGA) is situated on the north shore of Queens along the East River, approximately 6 miles east-northeast of Midtown Manhattan.

KLGA’s location within the broader NYC area, as seen in a Google Maps terrain view

Important Topographical Features: New York City is located in the extreme southeastern corner of New York State, bordering suburban New Jersey and Connecticut. These suburban regions combined with those in Long Island comprise the Greater New York City Metropolitan Area, which is the most populous urban agglomeration in the United States and one of the populous urbanized areas in the world with an estimated population of 18 million. New York City itself sprawls across the coastal plain around the Hudson River estuary. The terminal moraine formed by glaciers of the last Ice Age result in a ridge of higher terrain that cuts a swath from southwest to northeast across the boroughs from northern Staten Island, northern Brooklyn, southwestern through central and northeastern Queens. Otherwise, the city itself is low lying. This ridge varies in height between 200-400 feet, rising sharply from south to north, but tapering more gently north. North and west of the city (about 30-50 miles away), lie significant elevations of the Catskills (north), Poconos (west), Taconics that are part of the broader Appalachian Mountain Range. The elevations of the lower foothills can range from 1000-1500 feet. Some of the elevations in the Poconos and Catskills, west and north of KLGA respectively, peak between 2000-3000 feet. The open expanse of the Atlantic Ocean lies south of KLGA and New York City. Long Island Sound also lies east-northeast. The vast urbanized area of the NYC metropolitan region has significant effects on local microclimates via differential heating (urban heat island effect). KLGA is in a low-lying area sensitive to UHI effects and marine influences.

Per the Local Climatological Data report from the National Weather Service:

On winter mornings, ocean temperatures which are warm relative to the land reinforce the effect of the city heat island and low temperatures are often 10-20 degrees lower in the inland suburbs than in the central city. The relatively warm water temperatures also delay the advent of winter snows. Conversely, the lag in warming of water temperatures keeps spring temperatures relatively cool. One year-round measure of the ocean influence is the small average daily variation in temperature.
National Weather Service – NYC Office

Wind Patterns

Below is a wind rose – you can read more about how to interpret this chart here.

Frequency (percentage) of the single most common wind direction: Due northwest (12%).

Directions that are most and least common: Other most common wind directions include west-northwest (10%), due west (8.5%), and due southwest (8.25%). Least common wind directions are east-southeast (1.5%), due southeast (1.75%), and south-southeast (2.75%).

Direction(s) most likely to produce the fastest winds: Winds in excess of 21.4 knots (~25 mph) are most frequently found coming from due northwest. West-northwest, north-northwest, due northeast, east-northeast, and due south directions can also see less frequent winds over 21.4 knots.

Direction(s) least likely to produce the fastest winds: As is the case with several other months, the least common wind directions of due east, east-southeast, and due southeast also rarely seen winds in excess of 16.4 knots.

Impacts of wind direction on local weather: November wind patterns are a marked shift from the prior two months. Winds coming from the northwestern quadrant become prominent. Meanwhile, winds from the south and southwest decline in frequency.

In general, northwesterly winds bring cooler, drier Canadian air into the region following cold fronts. Northwesterly winds will tend to warm slightly because of compressional warming as they downslope coming off the higher terrain of the Catskills, and Poconos outside of the city. This can sometimes lead to warmer temperatures than would normally be expected for this wind direction. Northeasterly winds, on the other hand, are often related to backdoor cold fronts sweeping from the Canadian Maritimes, the onshore flow ahead of an advancing warm front, or a passing coastal storm to the south.

The pattern of winds in November suggests the prevalence of classic frontal systems moving through, where warmer southwesterly winds precede the passage of a cold front, behind which strong, gusty westerly and northwesterly winds pick up. Northeasterly winds are, as pointed out above, a sign of passing coastal storms.

Maximum observed two-minute wind speed for the month: 41 knots (47 mph).

Temperature and Precipitation Averages/Records

Temperature units are in Fahrenheit and precipitation is in inches.

Worth noting: Average high temperatures in November start falling into the 50s, while lows fall into the upper-30s. November is the first fall month in which no record high temperature exceed the 90°F.

Date	Normal High	Normal Low	Record High	Record Low	Record Lowest Max	Record Highest Min	Normal Precip	Record Precip
1	60	46	83	37	48	64	0.11	1.57
2	59	46	83	29	39	66	0.12	1.87
3	59	46	80	32	46	61	0.12	2.05
4	59	45	76	29	45	63	0.11	3.05
5	58	45	74	32	44	61	0.11	1.76
6	58	45	75	30	39	65	0.11	0.96
7	58	44	76	32	42	58	0.11	3.07
8	57	44	77	31	39	63	0.11	4.42
9	57	44	78	27	38	59	0.10	0.77
10	57	44	75	27	40	59	0.11	1.23
11	56	43	74	26	35	62	0.10	0.90
12	56	43	69	27	41	56	0.11	1.74
13	56	43	70	24	35	58	0.10	1.60
14	55	42	72	24	36	57	0.11	2.05
15	55	42	80	22	37	60	0.11	1.61
16	55	42	72	22	34	60	0.11	2.32
17	54	41	72	27	39	53	0.12	1.49
18	54	41	72	22	32	55	0.11	1.03
19	54	41	70	22	35	55	0.12	1.62
20	53	41	75	23	34	61	0.12	2.91
21	53	40	69	20	35	61	0.11	0.84
22	52	40	69	19	29	56	0.13	1.48
23	52	40	70	17	31	55	0.11	1.35
24	52	39	68	22	32	56	0.12	1.05
25	51	39	68	23	35	57	0.12	2.08
26	51	39	67	24	34	58	0.10	1.98
27	51	38	65	23	32	52	0.12	1.74
28	50	38	68	21	32	54	0.12	1.76
29	50	38	69	17	28	60	0.12	2.23
30	50	37	70	18	26	57	0.13	1.23
Range	50-60	37-46	65-83	17-37	26-48	52-66	0.10-0.13	0.77-4.42

NYC Weather Update – Nov 5, 2019

November 5, 2019Climate, NYC, Rain, Snowclimate, cold front, low pressure, new york city climate, new york city weather, new york city wx, nyc weather, nyc wx, rain, rain/snow, warm sectorLei Zhao

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 Weather Update – Oct 21, 2019

October 21, 2019NYC, Raincold front, low pressure, new york city weather, new york city wx, nyc weather, nyc wx, rainLei Zhao

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 Weather Update – Oct 14, 2019

October 14, 2019NYC, Rain, Thunderstorms, Weather Updatecold front, low pressure, new york city weather, new york city wx, nyc weather, nyc wx, rainLei Zhao

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 Weather Update – Oct 8, 2019

October 8, 2019NYC, Rain, Thunderstorms, Weather Updatecold front, high pressure, low pressure, new york city weather, new york city wx, nyc weather, nyc wx, rain, thunderstormsLei Zhao

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 (KLGA) Climatology for October

October 2, 2019Climate, NYCclimatology, cold front, high pressure, new york city climate, new york city weather, new york city wx, nyc climate, nyc weather, nyc wx, warm front, wind roseLei Zhao

Other Month’s Climatologies

January
February
March
April
May
June
July
August
September
November
December

Station Basic Information

City Name / Station ID: New York, NY (LaGuardia Airport – KLGA)

Local Geography and Topography

Station Elevation: 10 feet above sea level.

Station Location: LaGuardia Airport (KLGA) is situated on the north shore of Queens along the East River, approximately 6 miles east-northeast of Midtown Manhattan.

Per the Local Climatological Data report from the National Weather Service:

On winter mornings, ocean temperatures which are warm relative to the land reinforce the effect of the city heat island and low temperatures are often 10-20 degrees lower in the inland suburbs than in the central city. The relatively warm water temperatures also delay the advent of winter snows. Conversely, the lag in warming of water temperatures keeps spring temperatures relatively cool. One year-round measure of the ocean influence is the small average daily variation in temperature.
National Weather Service – NYC Office

Wind Patterns

Below is a wind rose – you can read more about how to interpret this chart here.

Frequency (percentage) of the single most common wind direction: Due southwest (9%). Note: due northeast is basically co-equal most common wind direction, perhaps only off by a fraction of a percentage point.

Directions that are most and least common: Other most common wind directions include due northeast (9%), due northwest (8.75%), and west-northwest (8.25%). Least common wind directions are east-southeast (1.8%), due southeast (2.75%), and due east (3%).

Direction(s) most likely to produce the fastest winds: Winds of 16.5-21.4 knots are most frequently found coming from due northwest. West-northwest, north-northwest, due northeast, east-northeast, and due south directions can also see less frequent winds over 21.4 knots.

Impacts of wind direction on local weather: October’s wind profile is a continuation on the trend established in September where wind frequencies begin to be distributed more evenly across the compass and less focused in the south. Winds from the northwest quadrant continue to increase in frequency, along with the frequency of the fastest winds coming from these directions. Northeasterly winds still figure prominently, though slightly less so than in September. Curiously, while southerly winds generally decreased in frequency, due southwest winds tick up slightly compared to September.

Northeasterly winds, on the other hand, are often related to backdoor cold fronts sweeping from the Canadian Maritimes, the onshore flow ahead of an advancing warm front, or a passing coastal storm to the south. Southwesterly winds are still capable of bringing in oppressive heat, as seen in the temperature section below.

Maximum observed two-minute wind speed for the month: 56 knots (64 mph) – this is the fastest recorded two-minute wind speed for any calendar month.

Temperature and Precipitation Averages/Records

Temperature units are in Fahrenheit and precipitation is in inches.

Worth noting: Even though average high temperatures in October fall into the 60s, it’s still possible to see summer-like warmth – you can see this from the record high of 95°F, set anew in 2019, and that record highs can reach into the mid-80s until late in the month. Overnight lows start to fall into the 50s and end up in the 40s by the end of the month!

Date	Normal High	Normal Low	Record High	Record Low	Record Lowest Max	Record Highest Min	Normal Precip	Record Precip
1	71	56	87	39	54	73	0.13	2.24
2	70	56	95	42	56	72	0.12	1.15
3	70	56	85	40	49	69	0.12	1.07
4	70	55	86	38	53	73	0.12	1.05
5	69	55	93	38	49	69	0.13	1.58
6	69	54	92	40	54	70	0.12	1.69
7	68	54	85	40	52	72	0.12	3.44
8	68	54	89	40	46	71	0.13	3.51
9	68	53	85	40	51	71	0.13	2.00
10	67	53	89	36	47	71	0.13	2.26
11	67	53	86	36	49	71	0.13	2.59
12	67	52	86	41	52	68	0.12	4.39
13	66	52	86	39	51	70	0.12	1.63
14	66	52	82	40	51	70	0.13	1.66
15	66	51	83	39	48	68	0.13	2.55
16	65	51	82	39	49	63	0.12	1.71
17	65	51	83	38	49	66	0.12	0.95
18	64	50	82	35	47	68	0.12	1.33
19	64	50	86	32	42	68	0.12	3.62
20	64	50	79	32	44	65	0.12	2.36
21	63	49	82	33	46	64	0.12	1.81
22	63	49	83	33	48	65	0.13	2.15
23	63	49	86	32	41	67	0.12	2.47
24	62	48	80	30	50	67	0.12	1.43
25	62	48	78	37	47	61	0.12	1.52
26	62	48	76	34	41	65	0.12	3.30
27	61	48	79	33	43	66	0.11	1.76
28	61	47	80	33	45	63	0.12	2.84
29	61	47	77	33	42	63	0.11	2.78
30	60	47	81	35	45	65	0.11	1.18
31	60	46	81	33	44	62	0.12	3.30
Range	60-71	46-56	76-93	30-42	41-56	61-73	0.11-0.13	0.95-4.39

NYC Weather Update – Oct 1, 2019

October 1, 2019NYC, Rain, Thunderstorms, Weather Updatecold front, high pressure, low pressure, new york city weather, new york city wx, nyc weather, nyc wx, rain, thunderstormsLei Zhao

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 – Sept 24, 2019

September 24, 2019NYC, Rain, Weather Updatecold front, high pressure, new york city weather, new york city wx, nyc weather, nyc wx, rainLei Zhao

A warm start to fall yesterday gives way to cooler, drier weather that will actually feel like fall. Much as was the case last week, high pressure will be in control over the area. This should lead to generally fair weather. However, there is some chance for rain Thursday as a cold front pushes through.

Rest of today – mostly sunny with high temperatures in the upper-70s. Overnight lows in the low-60s.

Wednesday – high temperatures again mild in the upper-70s with warming influence of downsloping northwest winds. Overnight lows in the mid-60s.

Thursday – increasing clouds with high temperatures in the low-80s and overnight lows in the upper-50s. A chance of showers later in the day as a cold front approaches.

GFS model output for 2 meter above ground level temperature and 10 meter above ground level winds at 8PM Friday

Friday – high temperatures in the mid-70s with sunny skies and overnight lows in the low-60s behind the cold front.

NYC Weather Update – Sept 16, 2019

September 16, 2019NYC, Rain, Weather Updatecold front, high pressure, new york city weather, new york city wx, nyc weather, nyc wx, rainLei Zhao

A weak frontal boundary passes through today. Behind this, high pressure will build and extend into the weekend. This persistent high pressure will result in mostly sunny conditions. Below normal temperatures in the low-70s will accompany northeasterly flow but a warming trend is forecast for the weekend as the center of high pressure shifts to the east.

Rest of today – mostly cloudy with a cold front pushing south then stalling out. Chances for light rain linger through the day. High temperatures in the upper-70s. Overnight lows in the low-60s.

High resolution rapid refresh simulated radar for 5PM today, showing some scattered light showers

Tuesday – high temperatures cool off into the low-70s behind the front. Winds turn to the northeast as high pressure builds over central Quebec. Overnight lows around 60°F but could dip into the upper-50s.

Wednesday – mostly sunny with high temperatures in the low-70s and overnight lows in the upper-50s.

GFS model output for surface pressure and winds valid at 2PM Thursday. The area of high pressure over the Northeast will serve to keep our weather fair, while pushing Hurricane Humberto safely out to sea.

Thursday – high temperatures remain in the low-70s, overnight lows in the upper-50s. It will definitely feel like autumn has arrived a few days early!

NYC Weather Update – Sept 10, 2019

September 10, 2019NYC, Rain, Storms, Thunderstorms, Weather Updatecold front, high pressure, new york city weather, new york city wx, nyc weather, nyc wx, rain, thunderstormsLei Zhao

Temperatures are on an upward trend towards midweek. A cold front moving in from the north brings the chance for rain and thunderstorms tomorrow into Thursday. Behind the cold front, a brief cool down to below normal temperatures occurs before temperatures go back to above normal in the low-mid 80s over the weekend.

Rest of today – early clouds should give way to some partial clearing by the afternoon, high temperatures in the upper-70s. Overnight lows in the upper-60s.

GFS model output for 2 meter above ground level temperatures and 10 meter above ground winds at 11AM Wednesday. Noticeably warmer temperatures will accompany the shift to southwesterly winds.

Wednesday – high temperatures in the upper-80s, with a chance for scattered showers and thunderstorms later in the day as a prefrontal trough associated with a cold front approaches. Overnight lows in the low-70s with continued chances for showers. Overall, a much warmer and more humid feeling, summer-like day with southerly winds and the presence of a high pressure center south of the area.

Thursday – clearing skies with highs in the low-80s. Cooler and drier behind the passing cold front. Overnight lows in the low-60s.

GFS model output for surface pressure and 10 meter above ground level winds on 2AM Friday. Winds by this time are forecast to have shifted to the northeast and east. Onshore flow will keep temperatures cool on Friday.

Friday – high temperatures remain in the mid-70s, overnight lows in the mid-60s as high pressure builds in briefly to the north. This will bring a cooler, northeasterly onshore wind to the area.

LZ | Weather

Weather updates & posts for NYC region

Tag Archives: new york city wx

NYC (KLGA) Climatology for November

Other Month’s Climatologies

Station Basic Information

Local Geography and Topography

Wind Patterns

Temperature and Precipitation Averages/Records

NYC Weather Update – Nov 5, 2019

NYC Weather Update – Oct 21, 2019

NYC Weather Update – Oct 14, 2019

NYC Weather Update – Oct 8, 2019

NYC (KLGA) Climatology for October

Other Month’s Climatologies

Station Basic Information

Local Geography and Topography

Wind Patterns

Temperature and Precipitation Averages/Records

NYC Weather Update – Oct 1, 2019

NYC Weather Update – Sept 24, 2019

NYC Weather Update – Sept 16, 2019

NYC Weather Update – Sept 10, 2019