Shaun Tanner has been a meteorologist at Weather Underground since 2004.
By: shauntanner, 5:38 AM GMT on April 23, 2012
It wasn't that long ago, just last October, when a mighty early Autumn storm rolled through the Northeast and brought with it a healthy dose of snow. Places like Central Park, NY received inches of snow that not only broke daily snowfall records, but also snowfall records for the entire month of October...in one day.
One could easily have assumed, based upon that one storm and the previous Winter of 2010-2011, that the Winter of 2011-2012 would be one for the record books. Mother Nature does not like to be predicted that far in advance, and instead of a treacherous Winter, the Northeast and much of the rest of the country was treated to a mild, dry season.
Flash forward to tomorrow, Monday. The Arctic Oscillation that has kept the cold, polar air to the north of the country for the last several months is finally allowing some cold air to be pulled down into the eastern half of the United States. The result will be something that looks a lot like, well, Winter.
An intense 988 mb storm is pounding the Northeast Monday, centered around New York City. This storm will have several consequences.
Let the Rain Fall
Having originated over the Gulf of Mexico and coming from the Atlantic Ocean, this storm will have ample moisture. Most of this moisture will fall to the ground as rain, with over 3 inches possible in coastal areas of New England Monday. Nearly 3 inches are possible in the New York City area through Monday afternoon, this after 2 inches of rain fell on Sunday. Below is the precipitation forecast through Monday afternoon.
Coastal areas from New Jersey through southern Maine are under Flood Watches. Areas prone to flooding most likely will have flooding during and after this event, so please be aware. Remember, it is never safe to drive through standing water.
Severe weather watches and warnings in the Northeast. Note the green along the coast are Flood Watches. The white represent Winter Storm Warnings and Freeze Warnings.
This storm is carrying quite a cold pool of air with it that is producing substantial snow for parts of the Northeast. Weather Underground has a great daily snowfall predictor that is predicting up to 18 inches of snow in some of the higher elevations close to the border of Pennsylvania and New York. The white boxes in the severe weather map above denote where the Winter Storm Warnings are posted. These are warning of up to 18 inches of snow along with intense northeast to northwest winds up to 40 mph. This could create visibility problems for areas receiving this fresh new snow.
Current temperatures. Note where the cold air is.
There is absolutely no doubt that snowfall records will be broken by the time the storm is over. Places like Pittsburgh, PA have daily snowfall records of only 0.50 inches, making it possible to break many records with just a little bit of snow.
Ohio Valley Cold
The cold air to the west of the all of the aforementioned precipitation will create hazards itself Monday morning. Sub-freezing temperatures into the 20s are possible from northern Illinois through western Ohio, marking the second time in a couple months that the agriculture in the area could be hit by damaging frost. I believe it is safe to say that farmers in the area are taking any precautions necessary to protect their crops.
Below is an image of the expected mornings temperatures for the northeastern portion of the country. Note the widespread light blues, which represent freezing or sub-freezing temperatures.
Stay dry, warm, and safe, friends!
Updated: 5:41 AM GMT on April 23, 2012
By: shauntanner, 5:09 PM GMT on April 20, 2012
As we have been reporting all week, a soaking rain event is expected for the East Coast of the United States this weekend. We have been using three models to watch the progression of a storm that will initially dive into the Gulf of Mexico before moving into Florida late Saturday. All three models are in agreement of the driving rain likely pretty much along the eastern seaboard through Monday.
As the storm moves through the Gulf of Mexico, it will grab a tremendous amount of moisture from the warm gulf. This usually translates to a rain event for Florida, and this storm is no different as it makes its way across the Sunshine State Saturday evening through Sunday morning. The most recent HPC precipitation forecast for the period valid Saturday morning through Sunday morning (image below) calls for much of the state to receive over an inch of rain, with the wettest areas north of Tampa Bay receiving nearly 2 inches of rain.
After moving across Florida, the storm will take a hard left turn, traversing just off the East Coast Sunday and Monday. The storm will actually be quite broad with two centers. The models have consistently kept both storm centers off the coast until the consolidate into one storm center while moving inland Monday morning over the Mid-Atlantic/New England states. What this will mean is the heaviest rain will fall along the coast from the Outer Banks of North Carolina through Maine. Because the storm will move inland around New Jersey, expect the heaviest rain in the country in the period from Sunday morning to Monday morning to be the heavily populated area from northern New Jersey through Connecticut and Massachusetts. This area can expect over betwen 2-3 inches of rain (image below).
Of course, there is a chance the eventual storm track could be slightly more inland. This would lead to substantially more rain farther inland. A track farther off the coast will lead to drier conditions.
Watching the Drought
Florida and the Southeast have lived through an extended dry streak with very little rain the past few weeks. This has produced drought conditions (see image below) in the Southeast with much of the area current under "Extreme" or "Exceptional" drought conditions. Thus, it would be obvious to say that any sort of driving, soaking rain will be beneficial to the region. Florida looks to be the biggest potential benefactor from this storm, however, with only minimal amounts expect in adjacent areas of the Southeast.
Dry conditions along the entire eastern seaboard will also benefit from this strong storm.
How to Monitor the Storm
Since this storm will be a rainfall event, the best product to monitor the storm will be the WunderMap. This will give you a good indication of where it is raining, and where it will rain in the near future. While a couple inches of rain is not torrential, it could cause some flooding, especially in flood prone areas. Thus, also keep an eye on Weather Underground's Severe Weather map for the most up-to-date severe weather warnings in your neighborhood. We will also be updating our Twitter feed with periodic updates.
Stay dry everyone, and enjoy the rain if you so desire
Updated: 5:32 AM GMT on April 21, 2012
By: shauntanner, 10:07 PM GMT on April 19, 2012
With the Southeast in a deep drought, it might be good news that a strong storm is set to impact the area Saturday through Monday. This storm will initially dive through the Southern Plains where it could produce a few severe thunderstorms. No large tornadoes are expected, but a few weak spin ups cannot be ruled out along the Texas coast. The Storm Prediction Center has issued a slight chance of severe weather in the area, with a general chance of thunderstorms from eastern Texas through much of the eastern third of the country.
The main event for the country will take place over the weekend as a strong storm will move through the Gulf of Mexico where it will pick up a tremendous amount of moisture. This moisture will translate to a lot of rain for Florida. The center of the storm is expected to move over the state Sunday. The most recent model predictions are suggesting that the storm will remain just off the East Coast as it moves northeastward Sunday and Monday. If this track validates, most of the heavy rain will fall off the coast. But if it takes even a slight jog to the west, expect ample rain from Georgia through the Northeast. Even if the storm remains off the coast, however, heavy rain is anticipated mostly in coastal areas along the eastern seaboard. Below is the HPC precipitation forecast from Friday through Sunday afternoon. You will note the heaviest rain will target Florida and the Southeast Coast through North Carolina as up to 3 inches of rain is possible. A couple of inches of rain is also expected for parts of the Northeast.
It is important to note that if this type of storm had developed in January, it would be an extremely strong nor'easter that would impact the entire eastern seaboard with extreme Winter weather.
Cool air will filter into the Upper Midwest and Northeast behind this storm. Expect maximum temperatures in the 40s and 50s by Monday in the northeast. Averages for this time of year are in the 60s.
By: shauntanner, 8:00 PM GMT on April 18, 2012
I have been forecasting for the state of Florida the past couple weeks and have been astounded by the general lack of rain not only for the state but for the Southeast specifically. This has aiding in the production of extreme drought conditions from eastern Alabama through South Carolina (including Florida).
Drought Monitor for drought conditions valid April 10.
Taking a look at the current precipitation statistics in parts of the South reinforces this reality. Atlanta, GA has received only .01 inches of rain thus far in April (normal 1.92), Birmingham, AL has received 1.23 inches (normal 2.56 inches), and Columbia, SC has received .50 inches (normal 1.62 inches). These numbers get even more amplified when you look at the year-to-date values.
So, needless to say, the region has a precipitation deficient and needs a good dose of rain. A deep trough of low pressure will dig into the Plains Friday before becoming a near cutoff low pressure system as it moves into the Gulf of Mexico. Any storm, not to mention a storm center, over the Gulf of Mexico will pick up a tremendous amount of moisture from the abnormally warm waters of the Gulf. After it does this, it will dump a couple inches of rain on Florida and adjacent areas of the Southeast. This is over a period from Sat - early Monday.
The storm will be on the southern end of a cold front that will move through the eastern third of the country Saturday and Sunday. Thus, after experiencing well-above normal maximum temperatures earlier this week, there will be a chance of snow in parts of the Northeast Sunday. The best chance of rain will be in northern Pennsylvania and Upstate New York and will not be widespread.
Below is the HPC prediction of rainfall amounts from early Saturday - early Monday morning. Note the maximum rainfall amounts of 3+ inches from New York through Virginia.
While this will not be a storm for the ages, it will bring a welcomed amount of rain east of the Mississippi Valley.
By: shauntanner, 5:16 AM GMT on April 13, 2012
The Storm Prediction Center has predicted a slight chance of severe weather for parts of Texas and Oklahoma this entire week, thus it should come as no surprise that the weekend holds the best chance of dangerous severe weather.
The Storm Prediction Center has issued an upgraded, high chance of severe weather from central Oklahoma through eastern Kansas (see image below). In addition, there is a moderate risk of severe weather from western Texas through southern Iowa, and a slight risk in the greater area from central Texas through southern Wisconsin.
I cannot stress the severity of this situation enough. Residents living in these regions should prepare for severe weather on Saturday.
What is severe weather, you ask? Severe weather can come in a variety of forms, including large hail, damaging wind, flooding rains, and even tornadoes. Thus, if you find that you live in the high risk area for Saturday (I'm looking at you, Oklahoma City and Wichita), then I would definitely make preparations for severe weather well before Saturday (that means start TODAY). Even if you are not greeted by severe weather, it is much better to be safe than sorry.
The best way you can keep yourself aware of any potentially dangerous weather in the area is to go buy a weather radio. Better yet, Weather Underground has a list of weather radio feeds where you can listen to the most up-to-date information regarding severe weather.
It is also important to keep appraised of severe weather before it hits your city. Most likely what will happen early in the day is the National Weather Service will issue Tornado Watches for the areas most likely to be affected by tornadoes. This absolutely does not mean tornadoes cannot form outside of these watches, so I would still keep an eye out for any development if you are anywhere close to the slight risk area. Weather Underground's severe weather map is a good resource to find what areas are currently under a watch or a warning. As Saturday progresses, thunderstorms will begin to develop. I might be slightly prejudice, but I truly believe the best way to track severe weather and thunderstorms in general is by using the WunderMap with the radar layer turned on. This will give you the most up-to-date view on where the thunderstorms are developing, and which way they are going. You can zoom into your town to see exact where any particular thunderstorms is.
Now, if one of these thunderstorms begins to have rotation, the National Weather Service will issue a Tornado Warning. This means that tornado formation could be imminent or a tornado has already formed. If you find yourself in a Tornado Warning area, TAKE COVER RIGHT AWAY. That means go to your basement and wait...with the weather radio turned on for the latest information. If you do not have a basement, go to the most interior room in your home, away from windows and doors. One of the safest places for you is actually in a bathtub in an interior bathroom.
Please stay safe out there on Saturday if you are in the Plains. Use good judgement, and make sure to prepare your neighbors who might not be aware of the potential for a severe weather outbreak.
As always, we will be covering any severe weather outbreak, minute-by-minute, on our Twitter account. All you have to do is follow us!
Updated: 4:13 PM GMT on April 13, 2012