SPC - No watches are valid as of Tue Jun 28 10:36:01 UTC 2022

No watches are valid as of Tue Jun 28 10:36:01 UTC 2022.

SPC - No MDs are in effect as of Tue Jun 28 10:36:01 UTC 2022

No Mesoscale Discussions are in effect as of Tue Jun 28 10:36:01 UTC 2022.

SPC Jun 28, 2022 0730 UTC Day 3 Severe Thunderstorm Outlook

SPC 0730Z Day 3 Outlook
      
Day 3 Convective Outlook  
NWS Storm Prediction Center Norman OK
0213 AM CDT Tue Jun 28 2022

Valid 301200Z - 011200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THURSDAY ACROSS
PARTS OF NORTH CENTRAL KANSAS...EASTERN NEBRASKA...WESTERN AND
NORTHERN IOWA...SOUTHERN AND EASTERN MINNESOTA...CENTRAL AND
NORTHERN WISCONSIN AND UPPER MICHIGAN...

...SUMMARY...
Strong thunderstorms may impact a corridor from the central Great
Plains into the Upper Midwest and adjacent Great Lakes region
Thursday, posing at least some risk for severe weather.

...Synopsis...
Blocking may continue to become more prominent, with an increasingly
amplified split flow developing across the eastern Pacific into
western North America during this period.  Downstream, a deep
mid-level low emanating from the Canadian Arctic latitudes is
forecast to continue to slowly dig near the southwestern shores of
Hudson Bay.  As it does, mid-level heights may become suppressed to
its south, across parts of the northern Great Plains through the
Great Lakes region.  Otherwise, there appears likely to be little
change to the persistent mid/upper ridging across much of the
central and southern tier of the United Sates.

In lower-levels, a developing surface low, emerging from the
southern Canadian Prairies on Wednesday, may progress across
northern Ontario, before perhaps deepening more substantively and
occluding across the southeastern Hudson Bay vicinity by late
Thursday night.  A trailing cold front appears likely to advance
south of the international border through much of the upper Great
Lakes region and northern Great Plains.  Along and east of
pre-frontal surface troughing, and around the western periphery of
low-level ridging centered over the southwestern Atlantic, a
seasonably moderate to strong low-level jet (30-40+ kt around 850
mb) may persist through much of the period across parts of the
southern and central Great Plains into the Upper Midwest and Great
Lakes region.  Although a gradual moistening, aided by the
northeastward advection of monsoonal moisture, may continue along
much of this corridor, seasonably high boundary-layer moisture
content might remain confined to much of the Southeast, lower
Mississippi Valley and southeast Texas.

...Central Great Plains into upper Great Lakes...
Although the strongest deep-layer mean wind fields may begin to
shift across and northeast of the Great Lakes region, 30-50 kt flow
in the 850-500 mb layer may persist across the Upper Midwest into
Great Lakes region through much of the day.  Farther south, the
stronger flow (on the order of 30 kt around 850 mb) will be confined
to the lower levels, east of the pre-frontal surface troughing into
the central/southern Great Plains.  Given sufficient
destabilization, this regime will at least conditionally support
organized severe thunderstorm development.

Despite some continued moistening of the pre-frontal boundary layer,
guidance suggests that modification of mid-level lapse rates,
associated with the remnants of a plume of elevated mixed-layer air,
may only allow for the development of seasonably modest mixed-layer
CAPE on the order of 1000-2000 J/kg.  Within the stronger deep-layer
mean flow, near and east-northeast of the upper Great Lakes, this
may be slowed or inhibited by early day cloud cover.

Still, this environment may support at least widely scattered strong
to severe thunderstorm development by late Thursday afternoon and
evening.  This may include isolated supercells, and a couple of
evolving clusters of storms, which could pose a risk for mostly
severe wind and some hail.

..Kerr.. 06/28/2022


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SPC Jun 28, 2022 Day 4-8 Severe Weather Outlook

Day 4-8 Outlook
      
Day 4-8 Convective Outlook  
NWS Storm Prediction Center Norman OK
0355 AM CDT Tue Jun 28 2022

Valid 011200Z - 061200Z

...DISCUSSION...
Medium-range guidance indicates that blocking with an amplified
split flow will remain prominent across the eastern Pacific into
western North America through next weekend and at least early next
week.  While a mid-level high remains centered over the Canadian
Yukon and adjacent Northwest Territories vicinity, large-scale
mid-level troughing is likely to maintained to its south, offshore
through inland of much of the U.S. Pacific coast.  

Downstream, after an initially deep embedded mid-level low finally
progresses offshore of the Newfoundland and Labrador coast and
weakens by early next week, broad mid-level troughing is forecast to
be maintained across much of eastern Canada and the Northeast.  At
the same time mid-level ridging will also be maintained from the
southwestern Atlantic through the southern Great Plains.  And
mid-level ridging within the westerlies to its north is forecast to
expand between the larger scale troughs, from the northern Rockies
eastward along the Canadian/U.S. border vicinity into the upper
Great Lakes region.

A cold front accompanying the deep mid-level low as it migrates
across and east of the southern Hudson/James Bay vicinity appears
likely to progress south of the international border, into the
Northeast by early Saturday.  Ahead of the front, it does appear
increasingly probable that at least a narrow corridor of more
substantive low-level moistening, across the northern Mid Atlantic
into southern New England, will contribute to destabilization near
the southern fringe of stronger westerlies (including 30-40+ kt in
the 700-500 mb layer).  While it currently appears that CAPE might
be limited by weak mid-level lapse rates, low-level lapse rates may
become fairly steep.  If CAPE were a little larger or low-level wind
fields a little stronger, the risk for organized severe thunderstorm
activity would seem a little more certain.  As it is currently
forecast, the environment probably will become at least marginally
conducive to thunderstorms capable of producing damaging wind gusts,
and it is possible that this could impact the urban corridor, at
least from the Greater Boston to New York City areas, perhaps into
the Philadelphia and Baltimore/Washington D.C. areas.

Late next weekend through early next week (including the July 4th
holiday), it is possible that one or two perturbations could emerge
from the Pacific coast mid-level troughing, and contribute to
potential for the evolution of organizing convective clusters across
the northern Intermountain region through northern Rockies. 
Eventually, this activity may work its way around the northern
periphery of the mid-level ridging near the central Canadian/U.S.
border area.  However, the predictability of these features at this
extended range remains low.


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SPC Day 1 Fire Weather Outlook

SPC Day 1 Fire Weather Outlook
          
Day 1 Fire Weather Outlook  
NWS Storm Prediction Center Norman OK
0134 AM CDT Tue Jun 28 2022

Valid 281200Z - 291200Z

...Synopsis...
An upper ridge will build into the Plains states from the west as a
mid-level trough amplifies across the Northwest today. Strong
mid-level flow will overspread a deep, dry boundary layer to the lee
of the northern Sierra, promoting Elevated dry and windy conditions
across the northern Great Basin during the afternoon. By afternoon
peak heating, isolated to potentially scattered high-based
thunderstorms are expected to develop across eastern parts of the
Great Basin into the Four Corners given ample monsoonal moisture
present. While the storms will be slow moving and producing rainfall
over areas that have received accumulations from preceding storms,
guidance still indicates that fuel beds are at least modestly
receptive to fire spread, with isolated dry thunderstorm highlights
maintained.

..Squitieri.. 06/28/2022

...Please see www.spc.noaa.gov/fire for graphic product...


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SPC Day 2 Fire Weather Outlook

SPC Day 2 Fire Weather Outlook
          
Day 2 Fire Weather Outlook  
NWS Storm Prediction Center Norman OK
0150 AM CDT Tue Jun 28 2022

Valid 291200Z - 301200Z

...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF WESTERN NEBRASKA INTO
FAR SOUTHERN SOUTH DAKOTA...

...Synopsis...
A mid-level trough will overspread the Northern Rockies and Northern
Plains regions as upper ridging persists across the southern and
central U.S. tomorrow/Wednesday. Strong flow behind the mid-level
trough will overspread the northern Great Basin, where downslope
flow along the lee of the Sierra will promote Elevated winds/RH
during the afternoon. Farther east, the combination of surface lee
troughing and the passage of a cold front will aid in the
development of critically dry and breezy conditions across portions
of the central Plains for several hours. Critical highlights have
been introduced since fuels are expected to be quite receptive to
fire spread following dry conditions. 

Meandering mid-level moisture across the eastern Great Basin will
continue to support the development of isolated high-based
thunderstorms by afternoon peak heating. While it is unclear how
much of an impact preceding day's rainfall will have on fuel beds,
at least spotty critically dry fuels would support ignitions from
lightning, with isolated dry thunderstorm highlights introduced.

..Squitieri.. 06/28/2022

...Please see www.spc.noaa.gov/fire for graphic product...


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