First Alert In-Depth: Beyond the 10 Day

ROCHESTER, N.Y. (WHEC) – Currently across the United states, we have a building upper level ridge over the Western US with a weak trough over the Eastern US. The troughing has contributed to our cooler weather throughout the majority of this week, but the upper level ridge to our west will move in and allow us to warm up for a brief period of time.

Further out we have a ridge building over the eastern Pacific which will contribute to the brief warmup, and the lobe of the Polar Vortex is beginning to move towards Greenland. However the warm up is brief, as mentioned before, as the pattern continues to meander between warm and cold locally.

This weekend, the ridge will be centered over the eastern US with a warmup expected as temperatures climb into the 60s! With the constant change in the weather pattern, this warmup does not last too long as a strong storm will switch us back to cold and bring a chance for snow on the backside. We have talked about this timeframe of stormy weather for a while now, and we are beginning to nail down the details on what to expect. We have talked about this storm being a cutter through the western Great Lakes, and that is exactly what it will do on Sunday. No high pressure to the north will leave room for the storm to cut north. This storm will bring us the milder weather, but also bring us some rain. The other story with this storm will be the wind. With the large temperature gradient between warm and cold we will watch out for strong gusts locally. An alert has not been posted for this storm as of Thursday morning, but the possibility continues to increase. As mentioned above, there will be a strong surge of cold air on the backside of this storm as a cold front rolls through. On the tail end of this cold front, we will have an area of low pressure form along it and slide south of our region. This, along with the cold air, will bring us a chance to see accumulating snow. Details of track and intensity need to be ironed out over the next few days, but be prepared for some snow locally Monday and into early Tuesday of next week.

After this storm the pattern continues to shift, and what may have been a progressive pattern the last few weeks will be showing signs of locking itself into a colder pattern locally. Towards the middle of next week, ridging that will be over the Pacific and ridging over the Norwegian sea will begin to move northward towards the North Pole. This will cause the Polar Vortex to split and slide into the mid-latitudes. One of the split lobes will once again find itself over the Hudson Bay. Also, models are signaling a trough sliding underneath the ridge over the eastern Pacific, which would lock the pattern in place. Due to the two ridges near the North Pole the cold air will be squeezed south and into the mid-latitudes, and with a lobe of the Polar Vortex over the Hudson Bay we will likely see colder weather arrive and take a stronghold locally next weekend and into the following week. The good news is that models do not show this lasting too long, but I am wary of that outcome due to the fact that models have a bias against atmospheric blocking. Obviously with the cold weather in place, we will have the chance for snow and an active pattern looks likely into the middle of March.

Our next storm chance after this weekend/early next week will come late next week and into the weekend (March 10-March 12). This timeframe has switched slightly since the last update, but the theme stays the same. This storm chance will come as the pattern shifts and bring in the colder weather locally. The jet dynamics continue to show extreme promise towards something along the east coast during this timeframe, but the question will be on if cold air slides in quick enough and if the energy phases at the right time for snow. Models continue to be back and forth on this system, but this timeframe looks very active across the Northeast for an area of low pressure to form and either slide over us with rain or slide east with snow. Timing of the northern stream of energy and southern branch of energy would need to be just right for snow with the lack of blocking over Greenland. Either way a storm is expected in this timeframe with wind also being a potential threat again.

After that, another storm chance is on its heels. The timeframe we are looking at will be March 14th-March 15th. This timeframe will be interesting to track, maybe not for something big but for a clipper to swing through from the northwest. Jet dynamics are not favoring anything along the coast as it is flat, but with the ridge out west something from the north will be favored. After the quiet start to March, it will be roaring like a Lion the next two weeks.

Our next update will come on Sunday, March 6th.

Temperatures: Mild through the weekend before turning cooler next week and remaining below average into the following week.

Precipitation: Above average the next two weeks.

Storm Chances:

March 6th-March 8th: Starts out mild with wind and rain Sunday before turning colder with wintry weather Monday & Tuesday. Strong gusts possible Sunday with freezing rain, snow, and sleet possible Monday & Tuesday.

March 10th-March 12th: Jet dynamics continue to favor low pressure along East Coast. Timing of energy phase will be important. Rain and snow possible. Wind will also be watched.

March 14th-March 15th: Alberta Clipper favored. Flat jet over the Southeast does not favor anything along the East Coast, but ridge west will favor something from the north.