523
FXUS63 KAPX 130254
AFDAPX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GAYLORD MI
1054 PM EDT SUN JUL 12 2026
KEY MESSAGES
-STORM CHANCES LATE THIS EVENING INTO TONIGHT WITH CONDITIONAL
SEVERE THREAT AND HYDRO CONCERNS. BEST CHANCES FAVOR EASTERN
UPPER AND FAR NORTHERN LOWER MICHIGAN.
-HEAT AND HUMIDITY SPIKE INTO MONDAY. HUMIDITY PEAKS MONDAY,
WHILE AIR TEMPERATURES PEAK ON TUESDAY. POTENTIAL FOR 100+
DEGREE TEMPERATURES IN NORTHEAST LOWER ON TUESDAY.
-RAIN CHANCES RETURN BY NEXT WEEKEND.
DISCUSSION
ISSUED AT 328 PM EDT SUN JUL 12 2026
PATTERN SYNOPSIS:
RIDGING PATTERN FIRMLY ESTABLISHED ACROSS THE CENTER OF NOAM, WITH
SIGNIFICANT PLUME OF HEAT BEING FORCED INTO THE GREAT LAKES WITH
TIME. TROUGHING OVER NORTHEAST NOAM WILL REINFORCE NW TO NNW FLOW
TONIGHT AS THE WARM ADVECTION WING ASSOCIATED WITH THE CORE OF THE
THERMAL RIDGE FORCES ITS WAY INTO THE GREAT LAKES TONIGHT. WITH N TO
NNE STEERING FLOW, RESULT WILL BE POTENTIAL FOR THUNDERSTORM
ACTIVITY TO DRIFT IN FROM THOSE RESPECTIVE DIRECTIONS LATER ON AS
STEEPER LAPSE RATES YIELD AMPLE ELEVATED INSTABILITY, IN CONJUNCTION
WITH A DIFFLUENT FLOW REGIME ALOFT... PERHAPS GIVING POTENTIAL FOR
DEEP CONVECTIVE PROCESSES. EVENTUALLY, THIS WING CLEARS THE REGION,
AND THE HEAT DIALS UP SEVERAL NOTCHES TO KICK OFF THE WORK WEEK.
INITIAL DEEP MOISTURE PLUME AT THE SURFACE WILL ALLOW FOR A HUMID
DAY ON MONDAY AS WELL, BEFORE THE CORE OF THE THERMAL RIDGE MOVES
OVERHEAD TUESDAY. RESULTING REDUCTIONS IN DEWPOINTS OWING TO
EFFICIENT MIXING WILL LEAD TO POTENTIAL FOR RARE-TIER HEAT ACROSS
PORTIONS OF THE REGION TUESDAY. EVENTUALLY, ANTICIPATING A
STATIONARY BOUNDARY TO FORCE THROUGH THE REGION LATE TUESDAY INTO
WEDNESDAY, BRINGING A REPRIEVE FROM THE HEAT, BUT REINTRODUCING RAIN
CHANCES WITH TIME.
DETAILS:
REST OF TODAY / TONIGHT- CURRENT CONVECTIVE TRENDS HAVE PREDICTABLY
BEEN POORLY RESOLVED BY ANY GUIDANCE... WITH CAMS REALLY STRUGGLING
TO GET A GRIP ON THE EVOLUTION OF THINGS, EVEN IN THE 12Z SUITE. A
FEW SELECT MODELS CAME CLOSE WITH ONGOING CONVECTIVE TRENDS OVER
WESTERN / CENTRAL UPPER MICHIGAN AND INTO LAKE SUPERIOR. CURRENT
SUBTLE TROUGH AXIS SPLIT BASICALLY RIGHT DOWN THE MIDDLE OF LAKE
SUPERIOR FROM NORTH TO SOUTH WILL CONTINUE TO BE THE FOCUS OF
CONVECTION THROUGH TONIGHT... AND THIS FEATURE IS SET TO SLOWLY
DRIFT SSE THROUGH THE CWA LATER THIS EVENING INTO TONIGHT. AMPLE
UNCERTAINTY REGARDING CONVECTIVE EVOLUTION... BUT WITH INCREASINGLY
STEEP LAPSE RATES ALOFT OWING TO AN EML ADVECTING INTO THE REGION
(PUSHING 8C/KM), ANTICIPATING ELEVATED INSTABILITY TO BALLOON WITH
TIME TONIGHT, ALONG WITH INCREASING SHEAR. AS SUCH, THERE WILL BE
THE POTENTIAL FOR CONVECTIVE COMPLEXES TO MATERIALIZE... AND WITH
ANTICYCLONIC FLOW IN PLACE... COULD SPELL A NORTH TO SOUTH STORM
MOTION. GREATEST DESTABILIZATION POTENTIAL WILL BE LATER TONIGHT, SO
IF ANYTHING GOES UP, THE POTENTIAL FOR SEVERE STORMS WILL BE
MAXIMIZED LATER TONIGHT. AS SUCH, SPC MAINTAINS A MARGINAL RISK OF
SEVERE STORMS OVERHEAD. PRIMARY CONCERN, OF ALL THINGS, WILL BE
LARGE HAIL... SOUNDING ANALOGS DEPICT SOME PRETTY LARGE HAIL
INSTANCES, AND WITH AMPLE STREAMWISE VORTICITY (AND REPORTS OF LARGE
HAIL WEST OF MARQUETTE ALREADY TODAY), CERTAINLY BELIEVABLE... AND
THERE IS POTENTIAL FOR SIGNIFICANT SEVERE IN THE EVENT THAT THE
ENVIRONMENT IS FULLY UTILIZED IN ANY STORM DEVELOPMENT OVER EASTERN
UPPER AND LEAKING INTO NORTHERN LOWER. IN ADDITION, LARGELY
RETROGRADING / SLOW STORM MOTION MAY SPELL HYDROLOGIC / FLOODING
CONCERNS WITH ECHO TRAINING. CERTAINLY GOING TO HAVE TO WATCH
CLOSELY, AS RAPID CHANGES ARE CERTAINLY ON THE TABLE.
MONDAY: IN THE WAKE OF THIS WARM ADVECTION WING, ANTICIPATING DEEP
MOISTURE POOLING TO TRANSPIRE OVER THE REGION, SPIKING SURFACE
DEWPOINTS TO NEAR 70 (SOME GUIDANCE SUGGESTS MID-TO-UPPER 70S, BUT
BASED OFF CURRENT UPSTREAM TRENDS, THIS SEEMS UNLIKELY, EVEN WITH
THE LAKES CONTRIBUTING MOISTURE). CONSIDERING SPIKING 850MB TEMPS,
ANTICIPATING A PRETTY FIRM CAP OVERHEAD DURING THE DAY... AND WITH
MINIMAL SYNOPTIC FORCING TO GENERATE A LIFTING MECHANISM, SHOULD NET
A DRY, ALBEIT HOT AND HUMID DAY MONDAY. THE WILD CARD? YE OLDE LAKE
BREEZE IN NORTHEAST LOWER... BUT CONCEPTUALLY, THIS FEATURE MAY BE
TOO SHALLOW TO COMPLETELY ERODE THE CAP. IN THE EVENT THAT THE CAP
CAN BREAK AGAIN MONDAY, THE ATMOSPHERE REMAINS PRIMED TO PRODUCE
STRONGER CONVECTION, BUT INCREASINGLY CONFLUENT FLOW ALOFT SUGGESTS
A SUPPRESSION TREND THAT CAN'T BE OVERCOME. AS SUCH, MOST OF THE
AREA LIKELY TO SPIKE IN THE 90S (WARMEST NE LOWER AND NEAR TVC,
ALONG WITH INLAND EASTERN UPPER... MID-UPPER 90S ON THE TABLE IN
THESE AREAS). COUPLED WITH HIGHER DEWPOINTS, HEAT INDICES TO SPIKE
96 TO 103 AREA-WIDE. TIGHTENING PRESSURE GRADIENT AND ACCELERATING
850MB FLOW SUGGEST A LACK OF RADIATIONAL COOLING MONDAY NIGHT...
WARMER GUIDANCE IS SUGGESTING WIDESPREAD LOWS IN THE MID-TO-UPPER
70S. CERTAINLY WILL BE A TOUGH STRETCH FOR THOSE SENSITIVE TO HEAT
ILLNESSES, ESPECIALLY THOSE WITHOUT ADEQUATE COOLING. AS SUCH, HAVE
OPTED TO HOIST A HEAT ADVISORY FROM MONDAY AFTERNOON THROUGH TUESDAY
MORNING TO COVER THE OVERNIGHT CONDITIONS AS WELL.
TUESDAY HEAT: CORE OF THE RIDGE TO PIVOT OVERHEAD INTO THE DAY ON
TUESDAY, WITH IMPRESSIVE 850MB TEMPS PUSHING OR EVEN EXCEEDING +25C
ON THE TABLE. WITH THE RIDGE AXIS BASICALLY RIGHT OVERHEAD,
ANTICIPATING SUPERB MIXING TO BRING VERY DRY AIR TO THE SURFACE,
PARTICULARLY ACROSS NORTHEAST LOWER MICHIGAN, AIDED BY DOWNSLOPING
NW WINDS. WILL BE A TOUCH OF A TEMPERATURE CONTRAST ACROSS THE
REGION... GENERALLY SPEAKING, THE HOTTEST AREA ON TUESDAY WILL BE NE
LOWER, SPECIFICALLY THE SAGINAW BAY AREA. IF WE CAN COMPLETELY MIX
THE PROFILE, IT IS NOT IMPOSSIBLE TO SEE ACTUAL AIR TEMPERATURES
APPROACH 105F IN THAT PARTICULAR AREA AIDED BY DOWNLOPING WARMING.
ELSEWHERE, ANTICIPATING HIGHS TO PEAK IN THE MID 90S OWING TO LAKE
MICHIGAN MODERATION, WITH THE EXCEPTION OF THE TVC AREA, WHICH WITH
DOWNSLOPING INTO THE CITY PROPER, LIKELY SEES TEMPERATURES SPIKE
INTO THE UPPER 90S. DID NOT RUN HEAT HEADLINES THROUGH TUESDAY OWING
TO THE LESSER HUMIDITY CONCENTRATION, AND THUS, LESS OF A DISPARITY
BETWEEN AIR TEMPERATURES AND HEAT INDICES. NONETHELESS, IN THE
WARMEST AREAS, PURELY FROM AIR TEMPERATURES, IT IS LIKELY AN
EXTENSION TO THE ADVISORY WILL BE NECESSITATED.
REST OF THE PERIOD: TROUGHING REGIME IN NORTHEAST NOAM TO DIG AND
EVEN RETROGRADE WESTWARD WITH TIME, WHICH WILL DRAW IN COOLER AIR
FROM THE NORTH, BUT WILL ESSENTIALLY PUT THE REGION IN THE HEART OF
THE BAROCLINIC ZONE BETWEEN THE EXTREME HEAT TO THE SOUTH AND MUCH
COOLER NORTHERN CANADIAN AIR. WITH THE HELP FROM SOME SYNOPTIC
FORCING, THIS SHOULD CONCEPTUALLY SPELL A WETTER CLOSE TO THE WEEK
AND PERHAPS INTO NEXT WEEKEND, AMID MUCH MORE SEASONABLE
TEMPERATURES.
AVIATION /06Z TAFS THROUGH 06Z TUESDAY/
ISSUED AT 1051 PM EDT SUN JUL 12 2026
MAIN CONCERN IS A CLUSTER OF THUNDERSTORMS CURRENTLY OVER NORTHERN
LAKE SUPERIOR THAT LOOK TO TRACK SOUTH INTO NORTHERN MICHIGAN LATE
TONIGHT/EARLY MONDAY MORNING. THESE STORMS WILL ENCOUNTER AN
INCREASINGLY UNFAVORABLE ENVIRONMENT WITH TIME AND WILL LIKELY
DISSIPATE AT SOME POINT AS THEY CROSS THE AREA, BUT STILL BRING THE
POTENTIAL FOR HAIL, GUSTY WINDS, LIGHTNING, AND BRIEF DROPS IN
VSBY ACROSS NORTHERN MICHIGAN -- INCLUDING PLN AND TVC.
OTHERWISE, VFR CONDITIONS ARE EXPECTED ACROSS NORTHERN MICHIGAN
INTO MONDAY NIGHT. WINDS WILL INCREASE OUT OF THE SOUTHWEST
MONDAY MORNING, EVENTUALLY TURNING TO WEST WINDS WITH GUSTS TO
15-20 KTS INTO MONDAY AFTERNOON.
APX WATCHES/WARNINGS/ADVISORIES
MI...HEAT ADVISORY FROM NOON MONDAY TO 8 AM EDT TUESDAY FOR
MIZ016>018-020>036-041-042-086>088-095>099.
MARINE...NONE.
DISCUSSION...HAD
AVIATION...DJC
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