Marine Weather and Tides
3/30/2021 -- ANZ330 has been split into ANZ331 and ANZ332. Click EDIT in Marine Forecast and select your new zone.
1/26/2021 -- The West Coast Satellite images havd been updated. They now use GEOS-17.
1/1/2021 -- The 7 day forecast are now working well. Thank you NOAA for your support.
|Sunrise 6:10AM||Sunset 9:10PM||Monday June 21, 2021 3:12 AM EDT (07:12 UTC)||Moonrise 4:48PM||Moonset 2:36AM||Illumination 86%|
7 Day Forecast for Marine Location Near Hamilton, OHHourly EDIT Help
Area Discussion for - Wilmington, OH  (on/off)  Help NOTE: mouseover dotted underlined text for definition
FXUS61 KILN 210705 AFDILN
AREA FORECAST DISCUSSION National Weather Service Wilmington OH 305 AM EDT Mon Jun 21 2021
SYNOPSIS. Showers and thunderstorms are possible at times today, as a cold front moves into a warm and humid air mass. Rain will continue into tonight, before drier air begins to move into the region for Tuesday. Temperatures will be below normal through the middle of the week, with warming conditions and storm chances returning at the end of the week.
NEAR TERM /UNTIL 6 PM THIS EVENING/. Thunderstorms are the main concern today, both early this morning and again in the afternoon.
The axis of a broad mid-level trough is currently over the upper Mississippi Valley, gradually moving east. A surface low near the Door Peninsula of Wisconsin is moving northeast into Michigan, with a cold front trailing this low to the southwest. A surface warm front extends ESE from this low across southern Michigan and into Lake Erie. Virtually everything south of the Interstate 96 corridor is in the warm sector of this system, with sustained southwesterly flow keeping temperatures and dewpoints fairly warm. The 3AM observation here at KILN is 75/68, but conditions are even more humid further north and upstream, with readings of 78/69 at KFWA and 79/71 at KOKK. SPC mesoanalysis indicates that these warm conditions are allowing for MLCAPE values of as much as 2000 J/kg across northern Indiana, with values even as high as 1500 J/kg (albeit with some inhibition) getting into the northwestern ILN CWA. The overall feed of theta-e, from 700mb on down, is not expected to subside through the rest of the morning -- though it may weaken slightly. What this means for the convective scenario is that there are no obvious signs, from an instability / theta-e perspective, that the ongoing mature QLCS is going to dissipate any time too soon. In fact, new development is occurring over western Indiana as of this writing, suggesting the overall convective complex may grow in size for a while (if not in strength). Current projections have this whole thing timed into Mercer County OH by around 09Z, and PoPs have been increased for the northwestern quarter of the ILN CWA from 09Z-12Z. Recent CAM runs seem much too anxious to dissipate this system and have been largely ignored.
While confidence in convection reaching the area this morning has increased, confidence that any of it will be strong is still low. Wind shear values (both 0-6km and 0-3km) are much stronger (and much better aligned directionally with the QLCS) across the northern few tiers of counties in Indiana. Shear is weaker, and more parallel to the convective orientation, further to the south. This would suggest that the threat for severe storms may be limited to northern Indiana and northwest Ohio, with just a low-end risk of some strong to maybe marginally severe winds in the northern parts of the ILN CWA (within a county or so of Mercer County OH).
The morning convection will likely, at least in some weakened form, make its way across the ILN CWA through the rest of the morning hours. This will not change the overall weather pattern, and replenishing southwesterly flow should allow for an increase in temperatures and instability ahead of the approaching cold front. However, as the surface front will already be making progress into the ILN CWA by as early as 15Z, the gradient in both temperatures and instability across the ILN CWA should be pronounced. For example, max temps for Celina OH are forecast to be in the upper 70s, while it would not be surprising to see Portsmouth OH / Vanceburg KY get close to 90 (if morning convection does not have an adverse effect).
Afternoon convective development, which will likely begin around 16Z-17Z, will be primarily focused in the southeastern half of the forecast area -- where instability (SBCAPE up to 2000-2500 J/kg) will be most robust. With this kind of instability, and 0-6km bulk shear values of around 30-40 knots, a few severe storms will be possible. No indications of a major event or big outbreak, but could be an event with a handful of warnings. Looks like primarily a wind/hail issue, with low-level directional shear not particularly impressive, but suppose a tornado may not be impossible in the more discrete early phase of the event. The overall deep-layer shear is relatively parallel to the orientation of the forcing, which is one factor that will keep this from being a bigger event. On the other hand, it may also lead to some training storms, so a low-end flood risk is also worth watching for. Any risk of hazardous weather should be cleared east of the ILN CWA by 00Z (if not a little sooner) once the surface front has moved out of the area.
SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/. Though the threat for convection will be over after the surface front has passed through the area, some additional rain is expected for several hours later in the evening and overnight. The 700mb cold front will be lagging the surface front by about 100-150 miles. Ahead of the mid-level trough axis, providing some forcing in a continued WSW feed of theta-e, a swath of rain is expected to move NE across the forecast area between 00Z and 09Z. Not expecting any heavy amounts out of this, but it forces leaving PoPs in the forecast through much of the overnight hours. Nonetheless, conditions will be cooling and drying in the low levels, with NNW surface flow helping to bring temperatures into the mid 50s to upper 40s for lows.
Very quiet conditions are expected Tuesday, as surface high pressure sets up on an axis that will extend through virtually the entire Ohio Valley region. This should allow for mostly clear skies, but with temperatures well below normal -- highs only around 70 degrees.
LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/. Surface high pressure will push east across the region Tuesday night through Wednesday night. This will provide for dry conditions with temperatures remaining several degrees below normal. Highs on Wednesday will be in the mid to upper 70s. Dry conditions will continue into Thursday as the high moves off to the east and we get into some developing southwesterly flow. This will help push temperatures on Thursday back to near normal with afternoon highs in the low to mid 80s.
A mid/upper level trough will then settle in across the central CONUS as we head into the weekend with an associated cold front pushing southeast into the region Saturday into Sunday. Ahead of this, a moist southwesterly flow pattern will persist across the Ohio Valley with PWs forecast to push up to around 1.75 to 2 inches Friday into Saturday. This will result in an increasing chance for showers and thunderstorms Friday and Saturday. Will then linger a chance for showers and thunderstorms into Sunday but this will be dependent on the exact timing of the cold front through the region. Highs on Friday will be in the low to mid 80s, cooling a bit to highs in the upper 70s and lower 80s for Saturday and Sunday.
AVIATION /07Z MONDAY THROUGH FRIDAY/. Dry conditions are expected through the rest of the overnight hours, with some mid and high clouds, and SSW winds increasing toward daybreak. Some gusts to around 20 knots are expected by 12Z.
Strong storms over northern Indiana are expected to weaken and perhaps at least partially dissipate before they arrive to this area. Nonetheless, there remains some chance that showers or storms could arrive by mid to late morning, prompting a VCSH in the TAFs. After that, there is a greater chance of new shower and storm development in the early afternoon. This period has been indicated with a -SHRA VCTS and MVFR ceilings, timed out to the most likely timing for storm development. Wind gusts will also get well into the 20 knot range during this time frame.
The storms should move out of the area by late afternoon, but some additional light rain may move back in after 00Z, indicated by another -RA or VCSH group. Winds will switch to the north tonight, diminishing to around 10 knots. OUTLOOK. Thunderstorms are possible on Friday.
ILN WATCHES/WARNINGS/ADVISORIES. OH . None. KY . None. IN . None.
SYNOPSIS . Hatzos NEAR TERM . Hatzos SHORT TERM . Hatzos LONG TERM . JGL AVIATION . Hatzos
Weather Reporting StationsEDIT (on/off)  Help NOTE: Click on distance to see the station location on a map
Airport ReportsEDIT (on/off)  Help Click EDIT to display multiple airports. Follow links for more data.
|Butler County Regional Airport, OH||4 mi||19 min||Var 4||10.00 mi||Partly Cloudy||79°F||69°F||72%||1004.6 hPa|
|Hook Field Municipal Airport, OH||13 mi||17 min||SW 12||10.00 mi||Mostly Cloudy||78°F||71°F||79%||1005.4 hPa|
|Cincinnati, Cincinnati Municipal Airport Lunken Field, OH||22 mi||19 min||S 8||10.00 mi||Mostly Cloudy||76°F||69°F||79%||1005.1 hPa|
Link to 5 minute data for KHAO
Wind History from HAO (wind in knots)
|1 day ago||Calm||S||Calm||S||Calm||SW||Calm||SW||SW||SW|
|2 days ago||Calm||Calm||Calm||E||SE||Calm||NW|
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