Warmer Today – Drought Monitor

We begin this week with thoughts of a fairly quiet weather pattern moving forward.  We even have a few chances of breaking the freezing mark.  Yesterday we reached 29° with a low of 1.6°.

Here is the drought monitor which I haven’t put up in a while.  Michigan has a wide swatch running from east to west with abnormally dry conditions.

With a few notable exceptions, the past week was mostly dry in the contiguous U.S. Heavy rain fell in southeast Texas this week, where large parts of ongoing drought or abnormal dryness saw improvement or full removal. Widespread precipitation of over a half-inch fell in the Pacific Northwest, though this was primarily in areas not experiencing drought or was not enough to result in improvements to drought conditions. Heavy snow fell in a localized band across parts of western Kansas and eastern Colorado, totaling 27 inches at Mt. Sunflower, Kansas. Snow also fell in the Denver area. These snow events allowed for improvement to ongoing severe and extreme drought. A powerful Nor’easter dropped heavy snow from eastern Virginia northeast into southern and eastern New England, though most of this snow fell in areas without drought. Mostly dry weather continued in Puerto Rico, where moderate drought expanded and severe drought was introduced. After heavy snow in December helped to build up high elevation snowpack in the West, particularly in California, very dry weather took over in January across much of the region, halting improvements to drought conditions and raising concerns about lagging snowpack if the drier weather continues as forecast. Finally, it should be noted that the large-scale winter storm affecting the central and southern Great Plains, Midwest, and parts of the eastern U.S. from the afternoon of February 1 through February 4 will not be accounted for until next week’s map.

Forecast Discussion

-- Today --

Weak radar reflectivity over Lake Michigan and southern Wisconsin
early this morning appears to be associated with weak isentropic
ascent around 700-600 mb where RH in the DGZ is a bit higher. Air
below this layer is fairly dry so much of this is virga. However
where lower levels are more moist and cloudy around Ludington, light
snow is being reported. Likely some seeder-feeder process going on
as the lake-induced boundary layer convection is too shallow and
warm to do much precipitating on its own. Models tend to fade out
this mid-level precip over our area during the day, though clouds
may persist, and can`t rule out some seeder-feeder snow where the
mid-level and low-level moisture overlaps north of Muskegon.

-- This afternoon through Tuesday --

We will be in the "warm sector" ahead of the low centered over Lake
Superior today and highs could top out in the lower 30s. This is not
a very robust wave in the upper levels in terms of vorticity
advection and upper level jet streak magnitude. The cold front
slowly passes through tonight into Monday morning, with a brief shot
of colder air behind it. Do have a mention of slight chance of
freezing drizzle at the onset of precip this evening/tonight (if
it isn`t snow) but icing amounts should be light. A light coating
of snow is possible by the end of Monday, with slightly more (half
to 2 inches) favored in the NW-wind lake effect belts. It will
take lake effect some time to get going behind the cold front as
the core of 850 mb cold air doesn`t arrive until midday Monday.
Again this lake effect convective layer is rather shallow, capped
at about 4000 to 6000 feet at only -15 C. Shortwave ridging and
warm air advection will shut off the lake effect for Tuesday.

-- Mid to Late Week --

GFS and ECMWF ensembles are tightly clustered with the temperature
forecast for Wednesday as milder Pacific air briefly washes over
Michigan, lending confidence that highs will climb above freezing
on Wednesday.

The next chance of light snow arrives with a loosely organized
clipper late Wednesday into Thursday. Good ensemble agreement for
a healthier upper level wave and surface low Alberta clipper
system late Thursday into Friday with a better chance of a couple
inches of accumulation. Longwave trough digs over our region for
the coming weekend, with cold air pouring in from northern Canada.