A brief review and your Northeast forecast
If there's one advantage to taking a break from blogging as long as I have; it makes for an easy recap. The winter was cold and snowy. The spring was beyond moist and the summer has been sizzling. How hot? How's does 108°F grab you on the tarmac at Newark Liberty Airport? Hot indeed, and three degrees hotter than the previous all-time record of 105°F. The Connecticut cities of Bridgeport and Hartford both broke their all-time record high temperatures, both recording 103°F. New York City's Central Park tied its 2nd hottest day ever at 104°F. The temperature at my backyard located in the pine forest foothills of the Catskill Mountains reached a blistering 95.6°F. Friday, July 22nd, 2011 will go down as one of the hottest days on record across the Northeast as a whole and one of three consecutive days of widespread 100°F heat with oppressive 80°F overnight "low" temperatures.
Records broken during heatwave of July 21-23, 2011
July 21st record high temperatures
July 21st record high minimum temperatures
July 22nd record high temperatures
July 22nd record high minimum temperatures
July 23rd record high temperatures
July 23rd record high minimum temperatures
What made this heat wave particularly intense were the incredible humidity levels. In conjunction with the Mississippi-like heat were Mississippi-like dewpoints in the upper 70's and low 80's. Even here the dewpoint briefly touched 80°F. The main culprit for such staggering amounts of atmospheric moisture associated with this heatwave was the equally staggering amount of precipitation which occurred during the springtime months over our region and all points upwind to the West Coast. I guess you can call spring 2011 flooding's Manifest Destiny. For the months of March-May the Northeast region as a whole saw its second wettest spring on record. Likewise for the Ohio and Mid-Mississippi Valley regions of the Country. Same for the Northern Plains and the Northern Rockies and not to be outdone, the Pacific Northwest recorded their wettest spring on record. The states of New York, Vermont and Pennsylvania also recorded their wettest spring on record and my tomatoes can attest to this fact.
Precipitation ranking by state for the period March-May.
Image showing statewide precipitation rankings for meteorological spring. Note many states broke their all-time record wettest spring from the Ohio Valley into the Northeast. (Credit: NCDC)
Precipitation ranking by region for the period March-May.
Image showing region-wide precipitation rankings for meteorological spring. Note the record to near-record precipitation across much of the northern half of the US. (Credit: NCDC)
The extremely wet spring heralded an early end to a seasonably cold and snowy winter for the southern two thirds of the Northeast, as heavy rains in early March quickly washed away the winter snowpack. The northern third of the region, for the second consecutive winter, saw mostly mild winter weather as a persistently highly positive phase of the Arctic Oscillation caused infiltration of maritime air on several occasions and kept most of the major blizzards south of the region. New York City's Central Park recorded its 2nd highest monthly snowfall total in January of 36.0" and 3rd highest seasonal snowfall total of 61.9".
Radar Image of December 26th, 2010 blizzard
Radar image showing the height of the Blizzard of December 26-27, 2010. Note the very heavy band of snow across northeastern New Jersey and the Hudson Valley of New York State. 20-30 inches of snow was common within this band, including New York City, which received 20.0" of snow at Central Park. (Credit: HPC/NOAA)
On a personal note (time for my little rant), these so-called blizzards (Dec. 26-27, 2010/Jan. 26-27, 2011) were the biggest tease snowstorms I ever did see. For all the hype, for all the state-of-emergencies, I received 4.1" and 3.2" respectively from those two storms. In fact my greatest snowfall of the "winter" occurred on March 23-24th with 7.9", more than those two storms combined! So, for this upcoming winter I'm expecting all those near-misses of last winter to be direct hits. And by expecting, I mean expecting like The Godfather expects things to get done...or else. In other words, I'm holding winter personally responsible should we not get at least three one-foot snowstorms. I don't know how I'll accomplish this but somehow us weather forecasters are viewed as conjurers of storms amongst some circles. So I'll see what I can do.
Northeast Weather Forecast
After the incredible high temperatures of last weekend a more seasonable pattern has taken shape over the last week for a majority of the Northeast. Most of the hot and oppressive weather has retreated south to the Mason-Dixon line where temperatures have continued to average in the 90's but elsewhere across the region a pattern more typical of mid-summer has taken hold - warm and mainly dry with a progressive pattern aloft bringing through several troughs and mid-levels disturbances to touch of scattered showers and thunderstorms. Once such trough is scheduled to move into the Northeast to begin the work week on Monday, with its parent mid-level low spinning down from Quebec to settle over Northern New England on Tuesday. Another disturbance will ride a quickening west-to-east flow into the region early on Wednesday and be accompanied by a stronger frontal boundary which should bring mainly dry and seasonable weather to the region to close out the week. Next weekend looks much more interesting as a trough drops down over the Northeast while a tropical disturbance approaches the East Coast. Chances are some deeper tropical moisture will be pulled into this trough axis giving the potential for heavy rains and downpours up and down the Eastern Seaboard.
Latest image of Atlantic Basin tropical disturbance '91L' (Credit: SSD/NOAA)
As of the August 2nd 5PM EDT National Hurricane Center advisory, the center of Tropical Storm Emily was located at 15.8°N, 65.4°W, moving west-northwest at 12mph. Maximum sustained winds have now strengthened to 50mph with higher gusts. Minimum central pressure is 1005mb.
The center of now Tropical Storm Emily formed very quickly yesterday evening near the island of Dominica and about 150 miles west of the mid-level center, which had been trying and failing to build down to the surface over the prior two days. Since forming, Emily has been able to maintain a central core of strong convection adjacent to the center of circulation. This convection has waned some earlier this afternoon but has now begun to reintensify, as evidenced by one overshooting thunderstorm top, and become consolidated closer to the center of circulation. Outflow is good to excellent in all quadrants, except the southwest quadrant where it's virtually non-existent.
The core of Emily is tucked right inside an area of high atmospheric moisture content with a warm sea-surface of 28°C and higher to travel over. Some dry air is noted to the northwest of the storm but not enough to preclude development over the next 24-36 hours as it approaches the southern shores of the island of Hispaniola. Being the case, it's a distinct possibility that Emily will be a minimal hurricane as the center either skirts the south side of the island or comes ashore on the Haitian side of the island. Interaction with the mountainous terrain of Hispaniola will disrupt Emily's development and it will likely be downgraded to a tropical storm, or even a depression, before emerging in the southern Bahamas during the afternoon hours on Thursday.
The long-range forecast for Emily becomes interesting once in Atlantic waters. Emily will be approaching the southwestern periphery of the Bermuda high and start to chart a course towards the northwest, taking the center straight through the archipelago. Environmental conditions at the end of the week appear favorable for steady strengthening, so Emily could once again be approaching hurricane strength by the time it reaches the northern Bahamas. It must be repeated that interaction with Hispaniola will have a tremendous influence in the eventual position and strength of Emily. This forecast is made with the assumption that Emily will track on the south side of the guidance envelope over the next 36 hours, limiting deterioration. Should Emily track more to the north interaction with Hispaniola will take a greater toll on the cyclone and re-intensification will be much reduced.
By this weekend Emily will be somewhere off the Southeastern US Coastline, likely regaining hurricane strength. Attention will be focused on an approaching trough of low pressure over the Great Lakes region of the country, which will begin to erode the western periphery of the Bermuda high and take Emily on a more northerly course. This path could take the center of Emily close to the Outer Banks of North Carolina and on up the East Coast to Cape Cod. Whether the cyclone as a direct impact on the Eastern Seaboard or not, tropical moisture from Emily will become entrained into the trough of low pressure approaching from the west, likely resulting in areas of heavy rain and thunderstorms this weekend from Canada to the Carolinas.
Current watches, warnings and advisories.
Current watches, warning and advisories issued by the National Weather Service. Courtesy of NOAA.
Radar: Northeast Region Loop
Radar loop of the Northeast region. Courtesy of Weather Underground.
Sea-surface temperatures off the Northeast Coast. Courtesy of NOAA.