Good news to report regarding Hurricane Joaquin – since yesterday, forecast models have arrived at a much clearer consensus regarding the track of Joaquin once it leaves the Bahamas – and the resulting forecast track takes it well east of the US East Coast.
This means we will luckily miss any severe impacts from a landfalling tropical cyclone. However, with Joaquin to the south and a ridge of high pressure to the north, continuous onshore northeasterly winds will still present moderate coastal flooding issues. Temperatures will likewise remain cool under the clouds and onshore flow, with rain expected to continue from today until Saturday. Lingering showers may persists on Sunday.
This week of damp, grey weather is leading up to a weekend when the uncertain future of Hurricane Joaquin may have an enormous impact on our weather. Since its formation earlier this week, Hurricane Joaquin has intensified steadily into a Category 3 storm currently spinning around the Bahamas. Joaquin’s future is still highly uncertain, and there’s been considerable spread between major forecast models as to where the storm will be at the end of the weekend. At this point, a landfall in the NYC region late this weekend is not out of the question.
Rest of today – cloudy and cool with high temperatures only in the mid-60s.
Friday – rain at times, windy and raw, with northeast winds in the 20-25mph range. It will feel like November with highs only in the mid-50s.
Saturday – similar to Friday in terms of sensible weather, with highs only in the upper-50s.
Sunday – this is where things get interesting depending on the track of Hurricane Joaquin. Depending on how closely Joaquin comes to hitting us, we could be looking at tropical storm conditions building through the day. If, on the other hand, it recurves out to sea, Sunday could be the best day of the weekend.
The Big Question: Where’s Joaquin Going?
Currently, Joaquin is a Category 3 storm over the Bahamas, with noticeable central eye, and symmetrical outflow in satellite images. Joaquin has been moving southwest along the edge of a subtropical ridge. Joaquin is an environment favorable for continued intensification, sitting over some very warm water with moderate wind shear.
Forecast Track
Over the last couple of days, forecast models have been set in basically two camps, one curving Joaquin northwest into North Carolina or Virginia. The other camp continues to point to a recurvature of Joaquin. Given the large spread between the models, National Hurricane Center forecasters have been emphatic about the degree of uncertainty with the track forecast up to this point.
Some major forecast models’ track forecasts for JoaquinOfficial NHC track forecast
Potential Impacts
Regardless of the landfall point for Joaquin, it will be contributing to a plume of tropical moisture leading to widespread heavy rainfall over a large portion of the east coast.
With the persistent northeast winds ahead of the northward advancing Joaquin, coastal flooding is also likely to take place in flood prone areas.
We have a simply splendid weekend on tap. Temperatures will be on the upward trend through the end of this week and into the weekend. The warm trend will continue into the beginning of next week, along with a return of more humid, dog days of summer type weather. Keeping an eye on the tropics, a great deal of uncertainty surrounds the future of Tropical Storm Erika, which could effect the U.S. East Coast in the long term.
Rest of today – beautiful, sunny skies with high temperatures in the low-80s. High pressure to the west is firmly in control, delivering this pleasant, seasonable weather.
Friday – almost a carbon copy of today, high temperatures in the low-80s with even fewer clouds as the high pressure center will be parked right over us.
Saturday – as the high pressure from the end of the week moves offshore and weakens, a subtropical high pressure center begins to take to control. This setup favors a warmer, more humid regime. Winds will shift to the southwest and temperatures will begin to climb into the mid-upper 80s.
Sunday – a longer term trend of warm and humid weather, typical of late summer, will continue Sunday. Temperatures will again be in the upper-80s. This trend looks to continue well into next week.
Tropical Storm Erika
A tropical wave that moved offshore of West Africa late last week has tracked across the Atlantic, strengthening along the way to become the fifth named storm of the 2015 Atlantic Hurricane season. Tropical Storm Erika, like its predecessor Danny, is having trouble maintaining its strength due to the influence of dry air and hostile northwesterly wind shear. Due to this shear, Erika’s center of circulation is actually still somewhat exposed (see below), and displaced away from its area of heaviest thunderstorms, which is concentrated in the southeastern quadrant of the storm.
The long term prospects for the storm are highly uncertain due to a number of factors. Erika looks to be tracking over Puerto Rico and may interact with Hispaniola (bringing much needed rain), which would significantly weaken the already feeble storm. This could lead to it dissipating entirely. However, should the storm make it past this area of high wind shear and possible land interaction, it’ll end up in the very warm waters around the Bahamas. This would provide the fuel for it to intensify quickly into a hurricane which could then threaten Florida and the East Coast. Definitely worth keeping an eye on.
Satellite image of Erika, with exposed center of circulation circled in red
We’ve certainly seen plenty of rain during the month of June, yet the NYC region remains in an area of moderate drought as of last Thursday. However, this does not reflect the rain that fell overnight Sunday into Monday. After a gloomy start to the week, we get a break of decent weather tomorrow, before another possible round of rain Thursday. The week ends with some drying out and improving conditions.
Rest of today – highs should top out in the upper-70s to around 80 today, with the potential for showers and thunderstorms later this afternoon. Storms have already formed to our west over northeastern Pennsylvania, but there is a stabilizing marine air layer over NYC and points east, so these storms may yet break apart before reaching us.
High Resolution Rapid Refresh model simulated radar for 1PM today.
Wednesday – skies will clear rapidly overnight and lead to a sunny, dry, and pleasant day on Wednesday. Highs should be near 80. The high pressure creating these pleasant conditions will not stay around long, as another warm front approaches from the west.
Thursday – will look a lot like today, with mostly cloudy skies, and a potential for showers and thunderstorms in the afternoon as a warm front nears the region. Highs will be a bit cooler in the mid-70s with the influence of clouds and a southeasterly flow off the ocean ahead of the warm front.
Friday – the warm front from Thursday is followed quickly by a cold front passing Friday morning. Behind this, high pressure takes control and brings decent weather for the first half of the weekend. Highs Friday should be in the low-80s with clouds and sun.
Tropical Storm Bill
Over the weekend, a disturbance organized over the western Gulf of Mexico, and by last night it had consolidated and intensified enough to be designated the 2015 Atlantic Hurricane Season’s second named tropical cyclone – Tropical Storm Bill. Bill will be making landfall imminently in Texas as a moderate strength tropical storm with maximum sustained winds of 60mph.
Satellite image of Tropical Storm Bill about to make landfall on the central Texas Gulf Coast
However, for people living in the path of Bill, it is not the wind but rather the potential for dangerous flash flooding that is the primary concern with this storm. Bill is forecast to bring as much as 10″ of rain over the next few days to parts of Texas, and upwards of 6″ for a wide swath of Oklahoma and Missouri. As you may recall, some of these areas were the scene of deadly flooding just a few weeks back, and the arrival of a rainmaker like Bill is most unwelcome for these areas that are still in the midst of recovering. Moisture from Bill will eventually work its way into our region, but in a much less intense way.
Yesterday, portions of our area got some much needed rain from a round of thunderstorms associated with a prefrontal trough. Today, we get another shot at rain and thunderstorms as the primary cold front actually pushes through. Behind that front, things cool off and dry out for Friday, before the humidity returns on Saturday. Things should stay dry Saturday, but we will see a more substantial chance at widespread rainfall Sunday with the passage of another cold front. Also of note, the National Hurricane Center released its outlook for this year’s Atlantic hurricane season, calling for a below normal season.
Rest of today – clouds give way to sun with warm temperatures in the mid-80s. Showers and thunderstorms are expected to form later this afternoon. The atmospheric setup today is a bit more favorable to showers and thunderstorms being able to persist into NYC and western Long Island, unlike yesterday when these showers essentially died out as they hit the stable marine air layer near the coast. The exact location of where storms form and move into will still be tricky to pinpoint even at this time.
High Resolution Rapid Refresh model output simulated radar for 3PM EST today.
Friday – once the frontal boundary passes through later today, it will usher in a much cooler and drier airmass for Friday. Temperatures should top out in the mid-upper 70s (still 5-10ºF above normal) under sunny skies.
Saturday – temperatures will be slightly warmer in the low-80s on Saturday with an increase in humidity as well. There could be a slight chance for scattered thunderstorms later in the day as well.
Sunday – another cold front passes through the region Sunday, bringing with it the chance for more substantial and widespread showers. Temperatures will also cool off to around normal, in the low-mid 70s.
2015 Atlantic Hurricane Season Outlook
The National Hurricane Center released its initial outlook for the 2015 Atlantic Hurricane Season that officially starts on June 1st. As you’ll see from the graphic below, forecasters are calling for a below normal season with 6-11 named storms (tropical storms with sustained winds greater than 39mph). Of these named storms, forecasters think 3-6 have a chance to intensify into hurricanes (maximum sustained winds greater than 74mph), and of those hurricanes 0-2 could become major hurricanes (Category 3 or higher, maximum sustained winds greater than 111mph).
The primary reason for the 70% probability of a below normal season is the disruptive effect of El Niño in the Eastern Pacific, which is known to alter the pressure and air currents over the tropical Atlantic, dampening the formation of hurricanes. On the other hand, the above average sea surface temperatures in the Pacific associated with El Niño are expected to induce an above average Pacific Hurricane/Typhoon season. Read the full statement from the NHC here: http://www.noaanews.noaa.gov/stories2015/20150527-noaa-hurricane-outlook-below-normal-atlantic-hurricane-season-is-likely-this-year.html
