Today was an active weather day for the NYC area, particularly over New Jersey and upstate. A funnel cloud was spotted up in the Albany area, and a few severe thunderstorms exhibiting strong rotation (the strongest thunderstorms-supercells-often feature a single internal circulation called a mesocyclone) formed ahead of a cold front that’s still slowly pushing its way over western New Jersey. Some of these storms produced large hail over interior parts of the NYC metro area.
Friday there will continue to be a risk for thunderstorms during the afternoon hours, otherwise it should be a mostly cloudy day with his right around 70.
In Oberlin, tomorrow should see skies gradually clearing with his in the mid-upper 60s.
NAM model simulated radar image for 5PM EDT Friday, May 23, 2014
Saturday still cannot rule out a lingering risk of thunderstorms and showers in the PM hours on Saturday as shortwaves (impulses of energy) continue to spin around the backside of the departing low pressure system that’s brought us this period of unsettled weather. Highs will again be around 70, depending on if breaks in clouds develop.
By Saturday, skies should clear out over Oberlin, allowing temperatures to rise into the low 70s.
NAM model simulated radar image for 2PM EDT Saturday, May 24, 2014
Sunday and Monday are still on track to be the best days of the Memorial Day weekend with temperatures in the upper 70s Sunday and low 80s Monday.
Camelopardalis Meteor Shower Visibility
Now about that meteor shower, will you be able to see it in NYC? Sadly, the answer is probably not, due to a forecast that calls for mostly cloudy skies. With cloudy conditions, light pollution is amplified as the light cast off from the city gets reflected back down even more. It will be a different story for Oberlin, though, where skies are forecast to clear due to the influence of building high pressure well before the anticipated peak of the meteor showers.
NWS hour by hour graphical forecasts. Red boxes indicate the forecast peak for the new Comet 209P/LINEAR Camelopardalis meteor shower. The blue line represents the percentage of the sky that’s forecast to be covered with clouds.
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.
First for weather headline that will be dominating today: the storm system that is set to bring us heavy, potentially flooding rain later today and into the overnight hours. Currently, temperatures in our area are generally in the mid-upper 60s with a strong south to southeasterly wind. This is leading to an influx deep moisture ahead of the approaching cold front. We are firmly entrenched in what meteorologists refer to as a warm sector. This will provide the necessary conditions for heavy rain and some possible embedded thunderstorms to form later.
NOAA NCEP surface analysis as of 9AM EDT. Note the cold front sitting just off to our west with an elongated area of moderate to heavy rain.
Based on the latest output from GFS and NAM models, it would appear the heaviest of the rain will arrive in our area during the PM rush and last through the evening into the early morning hours. So, if you’re going to be heading out this evening, grab an umbrella and appropriate rain gear.
NCEP’s forecast for quantitative precipitation totals over the next 24 hours.
One of the major hazards with this storm is flash flooding and flooding in general. Because a high amount of precipitation is anticipated to fall in a relatively short time window, flash flooding is a real concern especially in urban areas and small streams. This will make for a sloppy and slow evening commute. The flip side of the fast moving nature of this storm system is that it should clear the area fairly quickly, meaning that you runners out there should have slightly better conditions than previously forecast for the start and duration of the Brooklyn Half Marathon.
NAM high resolution model output showing the cold front and storm system to have pushed through our area by about 5AM EDT
Saturday after the cold front passes through and the rains subside, we should be looking at gradually clearing skies and slightly above average temperatures in the low 70s.
Sunday through Tuesday – we will be compensated for this rainy Friday by a string of days with fair conditions and seasonable temperatures. A high pressure center will form and camp out over our area, preventing any bad weather from impacting us. As such, temperatures should be nearly steady each day during this period in the upper 60s to low 70s with mostly sunny skies.
We’ve been fortunate that a persistent high pressure off of Nova Scotia has been stalling the arrive of a storm system earlier forecast to bring showers during the midweek period.
Our luck is about to run out, however, as the low pressure center and associated frontal boundaries will finally make their approach over the NYC area.
Thursday – overnight, a warm front is projected to pass through our area, bringing along a chance of drizzle, and the possibility for dense fog tomorrow morning as lower levels of the atmosphere become saturated with the coming southerly flow. Once the warm front passes over us, we will see a noticeable increase in temperatures, with highs forecast to be in the mid-upper 70s and possibly low 80s in interior portions of the region. Although the probability is low, there could be a couple showers and stray thunderstorms as well.
Friday – as the cold front associated with the low pressure center below draws closer, chance of precipitation will increase steadily during the course of the day. To start off, lighter showery precipitation should move in during the morning and early afternoon hours. Thereafter, heavier precipitation, and possibly thunderstorms, will move in especially during the evening and overnight hours. Due to the ground being somewhat saturated from the last round of rain we got, there could be some flash flooding in the heaviest down pours. Temperatures will be a bit cooler than Thursday in the upper 60s to around 70.
L and H correspond to approximate locations of surface low and high pressure centers. Notice the strength (high amplitude) of the associated upper trough and ridge
Saturday (BK Half Marathon Race Day) – good news for you runners out there as it appears the weather will cooperate for race day. The pesky slow-moving frontal boundary responsible for the rain on Friday will finally clear the area early Saturday morning, just in time for the start of the race. There may be some light showers early, but once the front clears conditions should start to improve. I would estimate start time temperature to be in the low 60s, with a high temperature forecast to be in the low 70s.
Simulated radar image from the North American Model (NAM) for Saturday at 8AM EDT
Sunday – a return to nice weather as the cold front has passed through and high pressure builds in temporarily. Partly cloudy with a high in the low 70s.
Hey folks, I got a special request to provide an weather analysis for the Brooklyn Half Marathon, which is scheduled for next Saturday, May 17th. A friend at the Road Runners informs me there are also pre-race activities going on at Brooklyn Bridge Park Pier 2 starting Wednesday.
Synopsis
First, in brief, I believe that Race Day itself should be dry, perhaps with a slight chance of showers but later in the day (as per the National Weather Service’s current forecast). Unfortunately, the mid-week pre-race activities won’t be quite as lucky as I’ll explain shortly. It is also worth noting that 6 days out, this forecast can still change, but I’ll be posting again Wednesday with a more up to date analysis.
Your Week
Moms are going to be thrilled that Mother’s Day today will be a spectacular day weather-wise. Subsequent to the passage of the cold front last night, today will feature clear conditions with warm temperatures in the upper 70s to low 80s and comfortable humidity.
Monday will be another nice day with summer like weather, temperatures right around 80 and increasing humidity due to the influence of the Bermuda High (which slowly shifts westward through the course of the spring into the summer, when it begins to dominate our weather with hot, humid air blasting from the southwest).
Tuesday a nearly stationary front will slowly push into our area, sparking the potential for some thunderstorms Monday night, and periods of showers during the day Tuesday (around 30% chance each of the following 3 days). Temperatures will be much cooler than Monday only in the low 70s.
Wednesday the stationary front above turns into a backdoor cold front (retrograde, progressing from east to west as opposed to the general pattern of west to east), continuing the potential for unsettled weather with periods of showers and a cooler day in the mid 60s.
Thursday brings another day of unsettled weather, with a series of weak impulses moving along a nearly stationary cold front just to our west. Temperatures will be slightly higher in the upper 60s.
Friday is the last day we’re stuck in this pattern of unsettled weather. The reason behind this prolonged period of unpleasant weather is the strong ridge of high pressure you see off the coast of Nova Scotia in the following upper air forecast from the Global Forecast Model. This strong high pressure will set up a blocking pattern on the trough of low pressure depicted. As this trough finally passes through our area, the best chance for steady showers and thunderstorms this week will occur. Temperatures will range in the mid-upper 60s.
Note the strong ridge that corresponds to an area of high pressure, and the trough that denotes low pressure to the west of the high
Saturday (Race Day) – at this stage, models seem to suggest that the cold front and low pressure system will have cleared New York just around start time on Saturday. Clouds should diminish during the day as the frontal boundary pulls away, however, can’t rule out a few spot showers lingering.
A batch of strong showers with some rumbles of thunder is approaching the NYC area. For the remainder of the afternoon and evening, strong to possibly marginally severe thunderstorms may pass through ahead of an advancing cold front. Damaging wind gusts and small hail are the primary threats.
Otherwise, expect broken clouds to cloudy skies and nice warm afternoon in the upper 70s to low 80s across the area. A line of thunderstorms is likely to fire up again later this afternoon into the evening hours as the cold front actually approaches.
Atmospheric instability is continuing to increase as we are in the warm sector ahead of the advancing cold front. Low level lapse rates and shear profiles are marginally conducive to the growth of some strong to severe thunderstorms.
We have a similar setup as last week that’s bringing overcast and rainy conditions to the region. A warm front well to our south is causing southeasterly/easterly winds off the cold Atlantic to stream in and saturate the atmosphere. Today, temperatures will be cooler with highs in the upper 50s.
Another mature cyclone with areas of precipitation and associated frontal boundaries
Unsettled weather conditions will continue Friday with the approach and passage of the aforementioned warm front. Temperatures will be warmer in the upper 60s, with a chance for showers and thunderstorms throughout the day.
Saturday looks like a warmer copy of Friday, again with the chance for showers and thunderstorms during the day and with increasing chance for precipitation in the evening/night hours as the cold front depicted above makes its way through. High temperatures will be in the mid 70s despite the cloud cover.
Sunday should be the best day of the weekend (just in time for Mother’s Day), with the frontal boundaries having passed over, skies should clear and allow for temperatures to top out near 80 in the city.
Monday the period of good weather continues to start the next work week, with high temperatures again possibly hitting 80 and mostly sunny skies.
It’s been a wild weather week that started with a tornado outbreak across half a dozen states in the South, and torrential rain fall that dropped as much as 2 feet in Florida, and as much as 6-8″ across the Northeast (resulting in incredible scenes like this landslide in Baltimore).
Fortunately, the weather has taken a turn for the better and will remain that way much of the coming week. This weekend is shaping up to be a nice one with temperatures on Saturday and Sunday reaching into the upper 60s to the low 70s across the region. There is a chance on both days of popup showers or thunderstorms in the afternoon, especially in inland areas with better daytime heating.
GFS model upper air (500mb absolute vorticity) output for this coming Wednesday. Note the strong trough out west (dip in the contour lines), and a ridge over our region (bulge towards the north of contour lines). Ridges correspond with high pressure and good weather while troughs denote low pressure and poor weather.
We’re finally turning the corner on warmer spring temperatures as the start to next week Monday-Wednesday will continue to feature high temperatures consistently in the low-mid 60s (about average). Dry and mostly sunny skies should also predominate as a ridge of high pressure (see above) builds in over our region.
Don’t be fooled by this gorgeous weather today (seriously).
A low pressure system forming in the lee of the Rockies, along with a nearly stationary frontal boundary draping down from a low moving into Canada will result in cloudy to mostly cloudy skies for the remainder of the week. There will be a chance for rain each day through Friday. The best chance for steadier rain will be late in the day Friday through Friday night and perhaps into early Saturday morning. This is associated with another area of surface low pressure and trailing cold front.
Note the frontal boundary draping across the region – this will give us a chance for showers each day Wednesday-Friday.
High temperatures will warm to near 60 Wednesday with a persistent south-southwesterly flow ahead of the aforementioned frontal boundary.
Thursday – with the influence of clouds and possible showery rain, temperatures will most likely hover around the mid 50s.
Friday – rain increasingly likely throughout the day Friday with high temperatures continuing to drop to around 50.
Saturday – temperatures will warm again into the upper 50s ahead of a cold front (and with a warm front forecast to swing through), however, it will be a cloudy day with a diminishing chance of showers through the day.
Sunday – the cold front will have passed through allowing for skies to clear, but temperatures will be cooler in the low 50s with winds from the northwest.
Next shot at precipitation comes Monday night into Tuesday with a surface low tracking from the Southeastern US.
Expecting a pleasant, mild, and mostly sunny day Saturday, temps in the mid-upper 50s – if you get a chance, definitely go out and enjoy the nice weather before a storm system enters the NYC region Sunday night into Monday night.
The mild temps today are as a result of southwest winds ahead of an approaching cold front. When the cold front pushes through, winds will shift to the west, ushering gusts up to 40mph and a significantly colder air mass.
Sunday – should be another mostly sunny day, though much cooler than today with highs temps only in the mid 30s. Sunday night, increasing chance of snow begins from south to north across the area. Overnight lows into Monday only in the mid 20s.
Monday – high temps will be right about freezing near the coast, and in the mid 20s in the interior. The setup for this storm system is very similar to the last snow storm (or non-storm) on Mar 3rd. Forecast models are suggesting that the bulk of moisture and favorable dynamics for heavy snow will remain offshore. Should this scenario hold, then we’d only expect to see a dusting to maybe an inch of snow in the city and Long Island, with negligible totals further north.
During the last storm, forecasters had difficulty resolving the uncertainty about exactly where the best conditions for heavier snow would exist. Again, this time, the line is quite close. A slight adjustment northward of the current forecast track for the low pressure system that is developing over the Gulf now could result in higher snowfall totals. See below how close the areas of darker blue representing moderate precipitation are to our area!
Tuesday – a dry and sunny day, but with temps still suppressed in the mid 30s in the city as a high pressure system temporarily sits over the NYC area.
Wednesday – the next low pressure system to impact the area will be moving in from the Great Lakes, with a low pressure center sliding to our north and a trailing cold front. Temps will climb into the low-mid 40s ahead of the cold front, so precipitation would be mixed to mostly rain.
The end of the week looks to be dry with highs near normal (around 47-49 deg at this time of the year).
