We start this week with a mixed bag of precipitation, currently rain, but eventually back to a wintry mix before ending. The rest of the week will be dry, with colder days on tap for the mid-week period before another warming trend to end things off.
Tuesday – once the storm system that’s responsible for today’s rain and mixed precipitation moves away, a cold front will usher in a strong area of high pressure that will dominate our weather for the mid-week period. This high pressure area will allow cold Canadian air to flow into the area from the north. High temperatures will struggle to reach the freezing mark, while a steady north wind will ensure wind chills in the teens.
Wednesday – will be similar to Tuesday in terms of sensible weather with highs in the low 30s, and partly sunny skies.
Thursday – another partly sunny day, but with slightly warmer temperatures in the mid-upper 30s, near normal.
Friday – should be essentially the same as Thursday with highs again in the mid-upper 30s. Doesn’t look like we’ll get any chance for precipitation throughout the end of the week and weekend.
This weekend will feature about normal temperatures for mid-December, with a small chance of rain/snow on Sunday. Relatively quiet weather during the weekend will give way to an active weather pattern for the first half of next week, with a robust storm system arriving Christmas Eve (all rain, sadly, so no white Christmas for us here in NYC).
Saturday – high pressure currently in control of the weather will erode as it moves east. Clouds cover will increase with high temperatures around 40.
Sunday – easterly winds off the ocean in the wake of high pressure centered over Atlantic Canada will bring some slight chance for precipitation. The lower atmosphere is fairly dry, and is not primed with moisture for precipitation. If precipitation does materialize, temperature profiles are low enough that some snow flakes could be seen, but the overall impact will be negligible. High temperatures will be in the low 40s with cloudy skies.
GFS model output for Sunday, 12/21/2014
Monday – a significant storm system will be approaching our region from the Central Plains. Forecast models point to a primary low pressure center over the interior of the country while a secondary low forms along the coast. Ahead of this storm system, some scattered showers could pass over the area Monday. Otherwise, expect a mostly cloudy day with high temperatures in the mid-40s.
Tuesday – coverage of precipitation will increase on Tuesday as that secondary low pressure center draws closer to the area. Warmer, marine air will be in place before a warm front passes over. This should ensure that temperature profiles remain warm enough to preclude the possibility of snow. Temperatures may rise to as high as the 50 degree mark Tuesday.
This early-mid week storm will cause some travel headaches for Christmas, but fortunately, it does appear the majority of precipitation will be in the form of rain.
We are still feeling the impacts of that Nor’easter that passed through Wednesday and Thursday. There will be some lingering showers east of NYC this morning, before gradual things begin to dry out and skies gradually clear from west to east. High temperatures will be in the mid-60s, but with a north wind blowing, it will still feel quite cool. We’ve got an excellent, fall weekend on tap.
Saturday – we’ll get sunny skies again, and high temperatures will remain in the mid-60s.
Sunday – much the same as Saturday.
Monday – high pressure will continue to build to our south. This will mean a shift in winds to the south and southwest, which will open the door for warmer air to stream in from the south. High temperatures in the mid-upper 60s, under sunny skies.
Tuesday – as that high pressure strengthens, we’ll get another day of even warmer temperatures Tuesday with highs near 70. We’ll be watching for another storm system approaching from the west that could bring us a chance of rain Wednesday.
We get one last day of late summer-like temperatures today before autumn comes back with a vengeance. A cold front has already passed through the city and you can already notice the winds beginning to shift to the northwest. This will herald a much cooler temperature trend. For the remainder of today, we can expect temperatures near 70 with some clouds building behind the front. There could be a sprinkle or two but nothing serious.
Sunday forecast map
Sunday will be noticeably more cold with high temperatures struggling to hit the mid-50s and with a gusty northwest wind. Gusts could top 30mph at times with sustained winds 15-25mph. Overnight lows into Sunday and Sunday night will be downright chilly in the 40s. Some interior areas could see frost Sunday night.
Monday the winds will abate as the pressure gradient between the departing cold front and high pressure to the west eases. Temperatures will remain cool at only around 60.
Tuesday and into later this week we will see the impact of a frontal system that moves through from the Great Lakes and develops as a coastal low off the Mid-Atlantic. Current models seem to suggest that this low will linger for a few days offshore, so we could see multiple rounds of rain as bands rotate around the storm center.
Winter Climate Outlook
The Climate Prediction Center has released its 3 month temperature and precipitation long range outlooks for the months ahead. As you will see, CPC has the NYC area in a zone of 33% chance of seeing a wetter and warmer than average winter. Call it a hunch, but I still think we’ll get a couple nasty Nor’easter type blizzards. Warmer than average of course doesn’t imply we won’t get freezing temperatures. A slightly warmer atmosphere would allow for more moisture and energy for coastal storms to feed off.
We’re still in the grips of a warm and humid airmass, despite some cooling off last night due to the passage of a weak cold front. This warm trend will not break until a stronger cold front passes through the region on Saturday.
Friday – expect high temperatures once again in the mid-upper 80s, albeit with increasing cloud cover as stratus cloud decks start to filter in ahead of the aforementioned cold front.
GFS model output for 2PM EDT Saturday
Saturday – unfortunately, the timing of the cold front above does mean it will bring adverse impacts to our weekend plans. Showers and thunderstorms are likely to precede and accompany this frontal passage, particularly later in the day Saturday into Saturday evening. High temperatures ahead of the front will remain warm in the mid-80s, somewhat cooler near the shore. There will be a noticeable cooling with this round of storms.
Sunday – Clouds will diminish through the course of the day Sunday as a much cooler regime works its way into the area. High temperatures will only be in the upper 70s for Sunday and the beginning of the weak.
Monday – Skies will be mostly clear, and temperatures will be much cooler in comparison to Labor Day, with highs only in the upper 70s (~10 degrees cooler than Labor Day). High pressure building over us will lead to an onshore wind flow, bringing in a cool, maritime polar airmass.
Two part update today – first to address NYC weather, and then to discuss the outlook for next week down in Brazil during the opening week of the FIFA World Cup.
Friday – the work week closes out with the wettest day so far with a warm front passing through tonight, and then a cold front following shortly thereafter tomorrow. This will translate to mostly cloudy skies, with a round of rain tonight, followed by a period of scattered rain showers and thunderstorms, and then ending with another round of heavier rain and thunderstorms Friday night. Temperatures will be much warmer than today after the passage of the warm front with highs in the low 80s.
NAM model output simulated radar image for Friday morning @ 5AM
Luckily for us, the cold front passes through quickly Friday and leads to a splendid stretch of weather beginning with a sunny, mild and pleasant Saturday and Sunday. High temperatures will be in the low 80s both days under clear skies. This is due to an area of high pressure building in from the west behind the cold front.
Warm Spell Next Week
This same high pressure area will track to the southeast during the weekend. By mid-week next week, the high pressure center will be offshore of the Southeastern US, and link up with the Bermuda High. As you may know, Bermuda Highs typically cause hot, humid weather in our region, and this will be no exception. Temperatures will steadily increase each day Monday, Tuesday, and Wednesday, such that by Wednesday, we’ll be looking at highs in the mid-upper 80s. This area of high pressure will also block any precipitation from impacting us until at least next Thursday into Friday when a low pressure system with a trailing cold front is forecast to pass through the Great Lakes.
GFS model output for next Tuesday
World Cup Weather
The World Cup is upon us!!! With opening kickoff just a few minutes away, I thought it’d be useful to talk about weather down in the host country, Brazil. As you know, it’s currently autumn in the Southern Hemisphere, but you wouldn’t be able to tell based on the forecast high temperatures for most of the Brazilian cities with games going on next week. High temperatures will range from the upper 70s-upper 80s depending on where you are.
The highest temperatures will be in Manaus, which not surprisingly sits in the Amazon basin. That’s also the city where you can expect the highest likelihood of rain and thunderstorms. Most of the coastal Brazilian cities that are hosting games will have pleasant conditions and high temperatures in the low 80s this week. Fair weather should be the story as high pressure will tend to dominate this week.
GFS model output for S. America on Tuesday
For your reference, here’s a map with dates of games being held in each host city. I’ll be keeping an eye on the weather and posting any relevant updates as they come up.
A lot of you may be going down to Governor’s Island this weekend to check out the Governor’s Ball this weekend, which promises to have spectacular weather for an outdoor music festival!
Today – winds from the north will diminish today as an area of high pressure builds in over NYC from the Ohio Valley. Temperatures will be seasonable near 80 with mostly sunny skies. If you’re on Governor’s Island itself, you might experience slightly cooler temperatures due to breezes off the harbor.
Saturday – day two of a weekend of glorious weather, as temperatures continue to climb with the high pressure sits right over us. Expect clear skies with warm highs in the mid 80s. Excellent weather for a grill out or just any outdoor activity period.
Sunday – yep, you guessed it, yet another day of ridiculously nice weather, with highs in the low-mid 80s, and a mostly sunny sky.
Next chance for rain and thunderstorms comes Monday in advance of a complex frontal system.
NWS Weather Prediction Center’s forecast for Sunday
For the remainder of today, temperatures will be in the low-mid 70s. A cold front is forecast to pass through the region later this evening into the overnight hours. Ahead of the frontal boundary, some scattered showers and a few thunderstorms are possible during the afternoon hours. Coverage will be sparse and any storms should be short in duration.
Saturday enough instability may linger in the wake of this cold front to allow for the development of PM pop up thunderstorms/showers. Again, coverage will be widely scattered and intensity of these storms would not be too great. Otherwise, partly cloudy with high temperatures will be slightly warmer in the mid-upper 70s.
Sunday will be the best day of the weekend with high pressure beginning to build into the area. This high pressure center is forecast to sit to the south of us, allowing a warmer airmass to circulate clockwise around it. This should translate to warmer temperatures in the upper 70s to low 80s (especially inland) across the area. Fair weather with mostly sunny to clear skies.
This warm trend should continue into Monday of next week, when highs again will push 80n across the area under mostly sunny skies. Next chance at rain will be Tuesday.
Weather conditions will gradually deteriorate through the course of the day today as an approaching storm system draws closer to our area. Cloud coverage, scattered showers, and possible thunderstorms associated with a warm front should increase in coverage during the course of the day. High temperatures should be on the mild side in the mid-70s.
Thursday – as of now, the National Weather Service calls for the aforementioned warm front to approach but not clear our region by Thursday morning. As such, cooler southeast and easterly winds off the ocean will keep temperatures on the cool side with highs only in the mid-upper 60s. There will be a persistence chance for showers and thunderstorms as multiple impulses of energy ride up and along the frontal system, with a break probably occurring between early Thursday morning and later Thursday afternoon/evening.
Friday – in NYC, although the warm and cold fronts associated with this latest storm are forecast to have cleared through the area by Friday, an upper level low situated over the Canadian Maritimes will continue to allow impulses of energy (shortwaves) to rotate into our area providing the spark for a continued chance of showers and thunderstorms, especially Friday afternoon and evening. This upper low will be slow to move east due to a strong blocking “omega” high pressure center located over the central North Atlantic. High temperatures will again be around the upper 60s.
For Oberlin, conditions will begin to improve earlier with the chance of rain ending by Thursday, partly sunny skies Friday with gradual clearing and highs in the upper 60s.
NAM output simulated radar image for Friday at 2PM EDTGFS model output of 500 mb heights and absolute vorticity for Friday at 2PM EDT
Saturday – we’ll see an tenuous area of high pressure trying to build in from our west. However, there may still be a marginal chance of PM showers. Otherwise, expect gradually improving conditions with temperatures climbing back up into the low 70s.
Sunday and Monday (Memorial Day) – These will be the best days of the weekend with dry, mostly sunny, and warm conditions. High temperatures will continue to climb into the mid-upper 70s Sunday and possibly topping 80 Monday (this applies to both Oberlin and NYC). Next chance at rain will be Tuesday.
A New and Spectacular May Meteor Shower? – About Comet 209P/LINEAR & Camelopardalis
A friend of mine brought to my attention that a newly discovered and possibly brilliant meteor shower is forecast to take place in the early morning hours of Saturday, May 24th.
In brief, Earth is forecast to pass through the debris trail of a comet “Comet 209P/LINEAR” (discovered in 2004) during the overnight hours Friday into Saturday. Researchers are forecasting that the debris trail Earth passes through is one that has accumulated dust from as early as 1800 to 1924. As such, expectations are that we could see about an average of 200-400 meteors an hour (some estimates call for a meteor storm of 1000 meteors an hour!), i.e. between about 3-7 meteors per minute. Furthermore, the setup for this event is such that Southern Canada and the East Coast of the U.S. are ideally positioned to view this event. In the image below, the red line represents the forecast position of the radiant line (point from which meteors appear to emanate and where you would see the highest number of meteors), note that this line runs almost direct over Washington DC. Also, notice that the moon is in waxing gibbous phase, reducing its potential to overpower the meteor shower.
Timing and Visibility
The forecast zenith of this meteor shower is between 2AM-4AM Eastern Daylight Savings Time on Saturday, May 24th. Right now, the forecast for this time window calls for mostly cloudy skies over NYC as well as points east and north (i.e. New England). Partly cloudy skies are forecast the points further south and west (i.e. along the Jersey Shore, Washington DC/Northern, Eastern Virginia, Western Pennsylvania), with the best viewing conditions being in the DC metro area and Eastern Virginia where mostly clear skies are forecast. A word of caution: cloud cover forecasts even this close to the day of are notoriously difficult to pin down due to the fact that even small changes in initial conditions can lead to large shifts in a forecast. However, with high pressure building over the east coast throughout the course of the weekend, we should have generally good chances to view this shower.
My recommendation is that you go check this out in an area with minimal light pollution if you can. I think we’re in for a what I hope will be a good show!
Where to Look
The radiant point for this forecast meteor shower will be situated in the relatively obscure constellation Camelopardalis (named by the Romans for a hybrid animal that looks like both a camel and leopard, now known as a giraffe). As you’ll see below, this constellation is located slightly below the North Star (Polaris), and a bit to the right of the Big Dipper.
You can read a more in-depth analysis of this meteor shower here. I’ve grabbed and edited a couple images from this entry.
All preliminary indications are that this Memorial Day weekend should see fairly good weather, as you can read in the detailed discussion below. First, for your work week forecast:
For the remainder of the day today, there is a slight chance of a pop up shower or thunderstorm as cumulus clouds continue to build. This risk will cease as the sun begins to go down, and cuts off the heat source for these clouds. Overnight lows will fall into the low 50s in the city (not as cold as last night, as some clouds are expected to stick around early and stunt the potential for good radiational cooling), with 40s in the interior.
Tuesday will be the best day of the week, with high pressure briefly building in from the west. This will lead to mostly clear skies and warm temperatures in the upper 70s (also partially due to an incoming warm front).
Beginning Wednesday, we will see a period of unsettled weather as a relatively slow moving storm system approaches. This system will develop over the Great Lakes, and a warm front is forecast to be approaching our area during the day Wednesday. There will be an increasing chance of showers throughout the day as the warm front nears, with the best chance for precipitation in the late evening and overnight hours. Temperatures will be slightly lower than Tuesday in the mid-70s.
HPC’s Day 3 forecast for the US
Thursday there is a bit of uncertainty regarding the eastward progression of the warm front mentioned above. If the warm front has already passed over us, then we’ll be in the warm sector between the warm front and approaching cold front. This would lead to favorable conditions for some thunderstorms. Otherwise, we would expect mostly cloudy skies and a chance for more showery precipitation. High temperatures will be similar to Wednesday.
Friday, with the cold front Thursday having moved through and high pressure slowly building in, we would expect a good day weather-wise. However, as you see in the following image, the center of the now occluded low pressure is forecast to remain nearly stationary off the coast of New England. This is due to a blocking high over the North Atlantic (not pictured). Therefore, a chance of showers is forecast for both Friday and Saturday, with skies gradually clearing from mostly cloudy to mostly sunny Saturday. High temperatures Friday is forecast to be in the low 70s.
Now, the all important initial weekend forecast: as depicted above, high pressure building over the Great Lakes should progress generally southeast towards the Carolinas during the weekend. This should translate into improving weather each day during the weekend and increasing temperatures. Saturday, Sunday, and Monday should see high temperatures climbing from the low to mid 70s, and skies clearing to become mostly sunny.
For those of you reading this forecast who are traveling towards Oberlin and points west, the forecast for those parts is actually even better than for New York City in terms of sunshine, although, as you know temperatures will be slightly cooler in Ohio than here.
