Sunday, April 23, 2017

Last Snowfall of the Season (?)



Sunday, April 16, 2017

A Wintry Mix, including freezing rain, possible for the Northern half of New Brunswick Update One

















A Wintry Mix, including freezing rain, possible for the Northern half of New Brunswick

















4:49 PM ADT Sunday 16 April 2017
Freezing rain warning in effect for:

Stanley - Doaktown - Blackville Area
Ice build-up due to freezing rain is expected or occurring.

A low pressure system will approach from the west tonight. Precipitation ahead of the low will begin as rain then change to freezing rain as temperatures drop overnight and persist into Monday morning.

Surfaces such as highways, roads, walkways and parking lots will become icy, slippery and hazardous. Take extra care when walking or driving in affected areas. Be prepared to adjust your driving with changing road conditions.

Freezing rain warnings are issued when rain falling in sub-zero temperatures creates ice build-up and icy surfaces.

Please continue to monitor alerts and forecasts issued by Environment Canada. To report severe weather, send an email to ec.weatheraspc.ec@canada.ca or tweet reports using #NBStorm.

Sunday, April 09, 2017

Snow Depth Record Set at Caribou, Maine - Updated 04/09/2017

There has been a foot or more of snow on the ground at Caribou, Maine since November 30th for a total of 131 days as of April 9th. This is the longest consecutive stretch with a foot or more of snow on the ground at Caribou. The old record of 120 days was set during the winter of 1968-1969. Weather record began at Caribou in 1939.  The snow depth is expected to drop below a foot early this week.

Sunday, April 02, 2017

Unexpected Winter Storm Theseus event summary


Friday, March 31, 2017

Spring Flood Potential Above Average throughout Northern and Eastern Maine

000
FGUS71 KCAR 310841
ESFCAR
MEC003-009-019-021-029-020845-WINTER/SPRING FLOOD POTENTIAL OUTLOOK
NATIONAL WEATHER SERVICE CARIBOU ME
441 AM EDT Fri Mar 31 2017

...SPRING FLOOD POTENTIAL OUTLOOK FOR NORTHERN... CENTRAL...AND
DOWNEAST MAINE...

This is the seventh spring flood potential outlook for 2017,
issued by the National Weather Service in Caribou, Maine. This
outlook is for northern, central, and Downeast Maine for the two-
week period from March 30 to April 13, 2017.

The spring flood potential for open water flooding is above
normal for all of northern, central, and Downeast Maine. The
potential for flooding due to ice jams is near to slightly above
normal across the entire region.

...CLIMATOLOGICAL GUIDANCE...

Colder than normal temperatures have been the norm through much of
March, with many locations across the state reporting monthly
average temperatures 4 to 6 degrees below normal. This cold has
allowed the river ice and snowpack to not only persist, but to
even grow in some instances. The weather pattern has been rather
active, though precipitation and snowfall amounts haven`t been
overly significant over the past two weeks.

This active pattern is expected to persist over the next several
days. The storm system that will affect the region over the
upcoming weekend isn`t expected to bring much in the way of
precipitation to the eastern half of the state, but forecast
models are indicating a series of low pressure systems will move
through the northeastern United States over the next couple of
weeks. At this time it is hard to say what impacts these systems
will have on our area; precipitation types and amounts will depend
heavily on what track each low pressure system takes, and the
long range models are showing little agreement on these sorts of
details. There are some hints that we may be breaking out of this
cold spell with a return to near normal temperatures, but there
could still be cold spells, especially if any of the storm systems
track to our south. Regardless, an active pattern means that we
could either hold on - or even add - to our snowpack or, if
warmer conditions do take hold, see several rain on snow events.

The official 6 to 14 day outlook from the Climate Prediction
Center for April 5 to 13 supports the above scenario, calling for
wetter than normal conditions, particularly over the next 10
days, with no strong signals for either warmer or colder than
normal temperatures.

...OBSERVED SNOW DEPTH AND WATER EQUIVALENTS...

As mentioned above, the snowpack has been very persistent the
past couple of weeks and, in fact, has even grown a bit over the
last few days. While portions of the Downeast coast and the Bangor
region are down to just a few inches of snow, much of the state is
still blanketed with 18 to 28 inches of the white stuff. In
particular, Aroostook County down into the Central Highlands have
the deepest snowpack, with a few locations reporting more than 30
inches. This lessens a bit as one heads toward the coast; the
Lincoln area down toward Bangor has 12 to 18 inches of snow. Most
areas have a near to above normal snowpack for late March. The
exception is the aforementioned portions of the Downeast coast
where the pack is 6 inches or less.

Perhaps more importantly, the snowpack holds a very significant
amount of water. The snow water equivalent, or the amount of
water held within the snowpack, is running 7 to 11 inches in much
of northern and central portions of our forecast area, with some
locations still reporting a foot or more of SWE. These numbers are
above normal, particularly in the Central Highlands where the most
water lies. The water content lessens as one heads toward the
coast; interior Downeast and the Bangor region generally have 4 to
7 inches of water, while the immediate coast has 2 to 5 inches of
water locked in the snowpack.

...SOIL MOISTURE AND WATER SUPPLY CONDITIONS...

Outside of far eastern Maine which is wetter than normal, near
surface soil moisture states across the region are generally near
normal. This drying out make sense given the cooler conditions and
reduced runoff. The latest Palmer Drought Severity Index, which
looks at soil moisture conditions in the longer range, is also near
normal across the entire state. Meanwhile, groundwater monitoring
wells, courtesy of the USGS, are variable around the region. The
Saint John Valley is showing above normal groundwater, while
portions of the Central Highlands and far Downeast Maine are below
normal. Wells across the remainder of our region are indicating
near normal groundwater conditions.

As has been noted in previous outlooks, the ground remains
unfrozen under the deep snowpack. This usually helps to slow
surface runoff because moisture is allowed to percolate through
the soil rather than run across it. However, given the very moist
near surface soils, the ground may not be able to readily absorb
runoff, especially if it occurs rapidly or in great amounts.

...RIVER AND ICE CONDITIONS...

River flows have been steady or decreasing over the past two
weeks as the colder weather and lack of significant rainfall has
slowed runoff. Some of the waterways in the Penobscot,
Piscataquis, and Saint Croix basins have showed some recent minor
rises as temperatures have been warm enough to allow for some
modest snowmelt, but the overall trend across the state has been
to hold steady or fall. In general, river flows are near to above
normal for late March.

River ice remains well entrenched across the northern and central
waterways. The Aroostook, Saint John, and Allagash Rivers are all
still mostly ice covered with a goodly amount of snow on top of
the ice. Some of the smaller streams still have some open
stretches. This holds true for the upper reaches of the
Piscataquis and Penobscot Rivers, as well. General ice states are
unknown, but with warming temperatures and some possible runoff,
it would be expected the ice should gradually weaken as we head
through early April. Downeast and coastal waterways, including
the lower stretches of the Penobscot, likely have little ice. No
additional ice strengthening or growth is expected from here on
out.

...IN CONCLUSION...

Based on the above information, the spring flood potential for
open water flooding is above normal across all of northern,
central, and Downeast Maine. Many rivers and streams are running
near to above normal, and soil moisture is likewise near to above
normal. There is plentiful water available in the snowpack, in
some cases nearly a foot or more. With an active weather pattern
expected and a likely turn toward warmer conditions, a rain on
snow and/or significant runoff event becomes more likely as we
head through early April.

The potential for flooding due to ice jams is near to slightly
above normal for those waterways that still have significant ice,
basically all of interior Maine. River ice has remained
substantial in coverage through March and has even grown a bit
since the warm spell in late February. No additional strengthening
is expected, but it will likely take another 2 or 3 weeks before
we see significant weakening and/or movement of the ice,
especially where substantial snow covers the river ice. Any
significant rain or snowmelt events during this time will have the
potential to cause ice movement and  ice jam flooding. The threat
is highest on the northern waterways, including the Aroostook,
Allagash, and Saint John Rivers, as well as in the upper
Penobscot and Piscataquis basins. This is where the ice is
thickest and covered with substantial snow. Overall this is not
an abnormal scenario heading into April, but with the anticipated
active pattern, a near to slightly above normal threat seems
reasonable.

It is important to remember that very heavy rainfall can bring
flooding at any time of the year, even in areas that don`t have a
significant snowpack.

The next spring flood potential outlook will be issued by NWS
Caribou on Thursday, April 13, 2017.

$$

Hastings

Snow Depth Record Set at Caribou, Maine

000
NOUS41 KCAR 300927
PNSCAR
MEZ002-302130-

Public Information Statement
National Weather Service Caribou ME
527 AM EDT Thu Mar 30 2017

...Snow depth record set at Caribou, Maine...

There has been a foot or more of snow on the ground at Caribou,
Maine since November 30th for a total of 121 days. This is the
longest consecutive stretch with a foot or more of snow on the
ground at Caribou. The old record of 120 days was set during the
winter of 1968-1969. Weather record began at Caribou in 1939.

$$

CB

Friday, March 24, 2017

Winter/Spring Flood Outlook issued on 03/16/2017 for Northern and Eastern Maine

...WINTER/SPRING FLOOD POTENTIAL OUTLOOK
NATIONAL WEATHER SERVICE CARIBOU ME
149 PM EDT Thu Mar 16 2017

SPRING FLOOD POTENTIAL OUT LOOK FOR NORTHERN... CENTRAL...AND
DOWNEAST MAINE...

This is the sixth spring flood potential outlook for 2017, issued
by the National Weather Service in Caribou, Maine. This outlook is
for northern, central, and Downeast Maine for the two-week period
from March 16 to March 30, 2017.

The spring flood potential is above normal for all of northern,
central and Downeast Maine, though it is closer to normal along
the coast. The potential for flooding due to ice jams is near to
slightly above normal across the entire region.

...CLIMATOLOGICAL GUIDANCE...

Below normal temperatures dominated the first half of March with
much of the region averaging 5 to 7 degrees colder than normal.
Precipitation averages were a little more variable; northern Maine
saw above normal precipitation while central and southern
locations were near to below normal for early March. This
precipitation generally occurred over 2 or 3 separate events with
short breaks in between. The most recent snow event brought
widespread 10 to 20 inches to the region, with northwestern areas
receiving the highest amounts. Most sites were reporting below
normal snow totals for the month prior to this storm. Now a
majority of locations are several inches above normal for mid
March and a foot or more above normal for the snow season as a
whole.

We don`t anticipate this overall cold and active pattern to alter
much going into the latter half of March. General upper-level
troughiness will persist over the next two weeks, keeping
temperatures generally near to below normal. Any warm-ups will be
brief. There will be the threat for precipitation, likely in the
form of snow, every few days, though these events should be
fairly minor through at least the next 7 days. A low is expected
to develop and strengthen off the East Coast this upcoming
weekend, but the model trends have been to keep it further
offshore, with little to no snowfall expected in our area. This
system will continue to be watched closely for any signs of a
westward shift, which would potentially bring significant snow
Downeast. Beyond this system, long range models are hinting at a
potentially stronger system around March 24 or 25, but it is too
far into the future to speak with any certainty.

Thus, with a fairly persistent trough across the northeast along
with several possible precipitation events, we anticipate below
normal temperatures and near normal precipitation over the next
two weeks. The official 6 to 14 day outlook from the Climate
Prediction Center for March 21 to March 29 supports this analysis.

...OBSERVED SNOW DEPTH AND WATER EQUIVALENTS...

The snowpack grew a fair amount after the most recent storm, with
most locations seeing 10 to 20 inches of snow. The snow depth is
now above normal across just about our entire region, particularly
the Central Highlands. The only exception is the immediate coast,
where the snow cover is a bit below normal.

The immediate coast is reporting 10 inches or less of snow cover
on the ground. This increases quickly as one heads inland; 1 to 2
feet is common across interior Downeast and the Bangor region.
Traveling northward into the Central Highlands and Aroostook
County, the snowpack is now 20 to 30 inches deep. The highest
terrain of the Central Highlands is covered with more than 3 feet
of snow; Chimney Pond`s latest observation indicated the snow
depth was estimated to be around 7 feet deep.

The snow water equivalent, or the amount of water contained in the
snowpack, is above normal across the Central Highlands, where 6 to
10 inches of water lies in the snow. The highest elevations have a
foot or more of SWE. This decreases across Aroostook County and
interior Downeast, where SWEs of 4 to 7 inches are common, with
locally higher amounts in excess of 8 inches. This is near to a
bit above normal for mid March. Further south, Bangor down to the
coast has 2 to 4 inches of water locked in the pack, with only an
inch or 2 along the coast.

...SOIL MOISTURE AND WATER SUPPLY CONDITIONS...

Near surface soil moisture states remain above normal, even
though runoff has slowed substantially during the colder
conditions. The latest Palmer Drought Severity Index, which looks
at longer-term soil conditions on the range of weeks to months, is
indicating near normal moisture conditions across the state.
Meanwhile, groundwater monitoring wells, courtesy of the USGS,
are mainly near to above normal. The exception continues to be in
the Central Highlands, which still have not caught up from last
year`s drought.

It should be noted that in areas where there has been a deep
snowpack through the winter, the ground is not frozen. This
usually helps to slow surface runoff because moisture is allowed
to percolate through the soil rather than run across it. However,
as noted above, near surface soils are moist, so the ground may
not be able to readily absorb runoff, especially if it occurs rapidly
or in great amounts.

...RIVER AND ICE CONDITIONS...

The recent spate of colder weather has allowed river flows to
subside as runoff receded. Flows are now generally near normal,
though southern streams are likely on the low side while northern
and central ones are higher. This trend will continue over the
next several days as no significant runoff events, either from
snowmelt or liquid precipitation, are anticipated. The
strengthening March sun should allow for some snowmelt, but this
will be minor.

The cold weather also allowed river ice to thicken and become
reestablished on some of the smaller streams that opened up in
late February. The Saint John River had some ice break up and
movement in the Allagash region during the February mild spell, as
well, but the river should be frozen again and any ice jams
locked in place. Although the ice cover may have strengthened a
bit with the colder temperatures, it is likely still weaker than
normal since hard black ice was never really established this
season. The snow that now lies on top of the ice will help to
protect the ice from the sunshine, but with the bitterly cold
temperatures (hopefully) at an end, little to no additional ice
growth is expected to occur.

...IN CONCLUSION...

Based on the above information, the spring flood potential for
open water flooding is above normal across all of northern,
central, and Downeast Maine, though it`s closer to normal along
the coast. This threat is mainly in the longer term as no
significant runoff events are anticipated in the near future.
However, the longer this deep snowpack and its substantial amount
of water lingers into late March or early April, the greater the
chance of flooding from sudden snowmelt and/or heavy rainfall.
With a cold and active weather pattern expected to continue
through the latter half of March, the snowpack is not expected to
diminish overly much. In fact, it may even grow if we do get some
more significant snow events. Therefore, an above normal flood
threat seems reasonable.

The potential for flooding due to ice jams is near to slightly
above normal across the entire region. Many of the mainstem rivers
are still mostly ice covered, and in fact, the ice has thickened
and become better established over the past couple of weeks. The
ice is still mostly comprised of gray or white ice, which is
weaker than the black ice that we normally see, especially on the
northern rivers. While weaker ice is more easily broken up, it is
less prone to prolonged jamming and/or significant flooding. As
with the snowpack, however, the longer that the river ice lingers,
the greater the potential threat of ice jams and flooding. It
would be ideal if the ice was allowed to simply sit and rot in
place. However, given the anticipated cold temperatures, the ice
will likely rot more slowly than what we might normally see. And
with an active weather pattern, the longer the ice sits, the
better the chances that a heavy runoff event will cause the rivers
to rise quickly and thereby "force" the ice to move before it is
in a substantially weakened state. With several positive and
negative factors, the ice jam threat is deemed to be near to
slightly above normal.

It is important to remember that very heavy rainfall can bring
flooding at any time of the year, even in areas that don`t have a
significant snowpack.

The next spring flood potential outlook will be issued by NWS
Caribou on Thursday, March 30, 2017.

$$

Hastings

Thursday, March 23, 2017

Surprise Eastern Maritimes Blizzard event summary

Weather summary
for Prince Edward Island
issued by Environment Canada
at 12:26 p.m. ADT Thursday 23 March 2017.

Discussion.

An intense low pressure system approached the Maritimes on Wednesday
and passed east of Prince Edward Island Wednesday night into
Thursday morning. Snowfall amounts ranged from 8 to 30 centimetres
across the island. The combination of freshly fallen snow and very
strong winds produced widespread whiteout conditions Thursday
morning.

The following is a summary of weather event information received by
Environment Canada as of 09 AM ADT.

1. Summary of snowfall in centimetres:

Wellington 9
Summerside 14
New London 8
Bonshaw 15
Harrington 9
Charlottetown 20 to 30
Grand Tracadie 18
Stanhope 12
Caledonia 11

2. Summary of maximum wind gusts in kilometres per hour:

North Cape 93
Summerside 93
Maple Plains 70
Harrington 78
Charlottetown 78
Stanhope 72
St. Peters 69
East Point 87

Please note that this summary may contain preliminary or unofficial
information and does not constitute a complete or final report.

End/ASPC