Monday, December11, 2017 L-36.com


Marine Weather and Tides
Rochester, NY

Version 3.4
What's New / NOTES
6/25/2017 - NOAA is having a major issue that impact the 7 day forecast load times. Many users are reporting problems. The issue has been reported.
5/23/2017 - Worked with NOAA again to speed up the 7 day forecast load times. Thanks to them for being responsive.
5/19/2016 - There were issues with the 3 day airport observation history. I switched to another data source. Let me know if you see any issues with the data feeds.

Sunrise 7:31AMSunset 4:37PM Monday December 11, 2017 5:37 PM EST (22:37 UTC) Moonrise 12:46AMMoonset 1:23PM Illumination 40% Phase: Third Quarter Moon; Moon at 23 days in cycle
NOTE: Some of the data on this page has not been verified and should be used with that in mind. It may and occasionally will, be wrong. The tide reports are by xtide and are NOT FOR NAVIGATION.
Marine Forecasts
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LOZ043 Hamlin Beach To Mexico Bay Along Lake Ontario Including Irondequoit Bay- 941 Am Est Mon Dec 11 2017
Rest of today..Northwest winds 10 to 15 knots becoming east 10 knots or less. A chance of snow showers late this morning. Waves 2 to 4 feet subsiding to 2 feet or less.
Tonight..Southeast winds 10 to 15 knots increasing to 15 to 20 knots. Snow. Waves 1 to 3 feet.
Tuesday..Southeast winds 15 to 20 knots becoming west. Snow. Waves 1 to 3 feet.
Tuesday night..Northwest winds 15 to 25 knots. Snow. Waves 3 to 6 feet building to 5 to 9 feet. Waves occasionally around 11 feet.
Wednesday..Northwest winds to 30 knots becoming west and diminishing to 15 to 20 knots. Lake effect snow. Waves 8 to 11 feet building to 9 to 13 feet, then subsiding to 5 to 8 feet. Waves occasionally around 16 feet.
Thursday..South winds 5 to 15 knots. A chance of snow showers. Waves 1 to 3 feet.
Friday..South winds 5 to 15 knots becoming west. A chance of snow showers. Waves 1 to 3 feet building to 2 to 4 feet. The water temperature off rochester is 42 degrees.
LOZ043 Expires:201712112215;;731460 FZUS51 KBUF 111441 NSHBUF Nearshore Marine Forecast National Weather Service Buffalo NY 941 AM EST Mon Dec 11 2017 For waters within five nautical miles of shore Waves are the significant wave height - the average of the highest 1/3 of the wave spectrum. Occasional wave height is the average of the highest 1/10 of the wave spectrum. LOZ043-044-112215-

7 Day Forecast for Marine Location Near Rochester, NY
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location: 43.17, -77.62     debug


Area Discussion for - Buffalo, NY
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Fxus61 kbuf 112149
afdbuf
area forecast discussion
national weather service buffalo ny
449 pm est Mon dec 11 2017

Synopsis
Strengthening low pressure system over the upper midwest will cross
the lower great lakes bringing a period of widespread snowfall into
Tuesday. Arctic air filtering in behind this system cold front will
bring a prolonged period of lake enhanced and lake effect snow south
and southeast of both lakes Tuesday night through Thursday.

Near term through Tuesday
Tonight, the surface high will exit the lower great lakes in advance
of a strengthening low pressure system currently over the upper
midwest. Warm air advection ahead of this system will result in
widespread light snow spreading across the lower lakes from west to
east. Snowfall accumulations from this initial round appears to be
on the light side with 1-3 inches possible by sunrise. An
additional 1-2 inches of widespread snowfall will be possible
Tuesday as the low slowly crosses the region. The highest amounts
will likely be found on the south facing slope of the tug hill east
of lake ontario where southerly upslope flow will greatly aid in
producing slightly higher amounts. The passage of this system and
its cold front will usher in a significantly colder air mass Tuesday
afternoon. 850mb temperatures will drop rapidly from -5c to -16c by
Tuesday evening. This arctic airmass combined with moisture wrapping
around the backside of the low will aide in the development of lake
enhanced and lake effect snows south and southeast of both lakes
Tuesday night.

Temperatures wise, ahead of the cold front expect highs to top out
in the 30s before rapidly drop back in the 20s with snow and blowing
snow likely as winds strengthen behind the cold front.

Short term Tuesday night through Thursday night
A complex scenario will continue to unfold Tuesday night and
Wednesday, with wrap around snow and lake enhancement increasing.

From a synoptic standpoint, a surface low will continue to deepen
across northern new england and southeast quebec as a deep mid level
trough closes off into a sharp closed low. The deepening system to
our east will allow for deep wrap around moisture to move back into
our region Tuesday night along and behind a secondary cold front.

Wrap around upslope snow will continue to support a general,
widespread light snow across much of the region.

Lake enhancement and upslope flow will play an important role in the
placement of the heavier snow amounts during this period. 850mb
temps plummet to around -16c. With the strong cold advection, the
favorable dendritic crystal growth zone will descend down into the
lowest 5k feet of the column by Wednesday morning, which is a
favorable setup for lake enhancement as the dendritic crystal growth
zone is seeded by light synoptic snow from above, setting up a
seeder feeder mechanism.

Off lake erie...

farther removed from the synoptic system, this will be a little more
of a pure lake effect scenario by later Tuesday night and Wednesday.

With this in mind, and in collaborating with our neighbors to the
west and south, we have called this warning area a lake effect snow
warning. Lake enhanced upslope flow will continue Tuesday night and
Wednesday morning along the chautauqua ridge, with upslope also
extending into the boston hills of southern erie county, and the
higher terrain of wyoming county. There will also be a strong
upstream connection to lake huron at times Tuesday night, which will
focus primarily on chautauqua county.

In northwest flow cases, the higher amounts focus along the higher
terrain just inland from the lake, where 10-15 inches storm total
may occur from tonight through Wednesday evening. If the strong lake
huron connection verifies, local amounts may approach 20 inches
across the higher terrain in western chautauqua county. Amounts will
be considerably lower along the lake erie shore without the benefit
of upslope flow. Amounts will also drop off quickly moving inland
from central cattaraugus county across allegany county.

Off lake ontario...

wrap around snow and possibly a deformation zone will become lake
enhanced Tuesday night and Wednesday from the rochester area east to
oswego county. The boundary layer flow will average about 300
degrees during most of the lake enhancement, which should direct
most of the lake enhancement from the east side of rochester
eastward to oswego county, with less lake enhancement west of
rochester. The greatest snowfall rates are likely to be from late
Tuesday evening through Wednesday morning when the lake enhancement
peaks, with snowfall rates slowly decreasing Wednesday afternoon as
the deeper synoptic scale moisture pulls away.

A larger portion of the snow in this area will be synoptic in
nature, with lake enhancement towards the second half of the event.

With this in mind, went with a winter storm warning in this area.

Expect storm totals of 9-14 inches over the two day period.

East of lake ontario it will be purely a synoptic event for
jefferson and lewis counties. The highest totals will be across the
tug hill plateau, which will initially get southerly upslope flow
tonight and Tuesday, then northwest upslope flow Tuesday night and
Wednesday. This should allow totals of 10-16 inches for the tug
hill. Elsewhere across jefferson and lewis counties, expect more on
the order of 6-10 inches storm total.

It will become quite windy later Tuesday night and Wednesday as the
low deepens to our east. Expect gusts of 30-40 mph to be common
across the entire area, with the strongest winds southeast of lakes
erie and ontario. Temperatures dropping into the teens will allow
the snow to be powdery, with significant blowing and drifting snow
developing. Finally, the wind combined with colder temperatures will
drop wind chills into the single digits below zero Wednesday
morning.

Wednesday night and Thursday some lake effect snow will continue
southeast of the lakes, with additional light to moderate
accumulations possible. This will gradually taper off later Thursday
and Thursday night as inversion heights lower some, and boundary
layer flow becomes more light and disorganized. A weak clipper
passing to our south may bring some general light snow mainly south
of the thruway Thursday.

Long term Friday through Monday
Latest 12z guidance has trended considerably colder across all
models as compared to the last couple of days. All of the models
are trending deeper with the longwave trough over the eastern u.S.

During the second half of the week, such that even though the trough
will still weaken this weekend, temperatures are now progged to only
warm to the mid 30s at most by Sunday. Otherwise, readings should
remain near or below freezing for Friday and Saturday.

Regarding precipitation, we will remain in an unsettled pattern as a
series of fast-moving low-pressure systems are expected to impact
the area. Given the fast-moving nature of the systems within the de-
amplifying pattern, significant timing differences exist between
models, and confidence in specific timing and location of
precipitation is low at this time. However, with two systems likely
affecting the region, one Friday night Saturday and a second
Sunday Sunday night, snow showers can be expected, with minor
accumulations possible Friday night into Saturday morning. Depending
on the track of the second system, we may see mixed precipitation on
Sunday, however if the the colder trend in the models continues,
this may end up staying all snow.

Aviation 22z Monday through Saturday
Widespread MVFR CIGS south and east of both lakes will persist
across the forecast area this evening. Additionally, a few locations
may see some very light snowfall or flurries. Otherwise, little
impact expected at the TAF sites this evening.

Tonight, deteriorate conditions from west to east as low pressure
advances eastward across the great lakes with developing widespread
light snow across the region with MVFR ifr.

Ifr with widespread light snow Tuesday as deepening low pressure
will slowly cross the lower great lakes. Behind this system much
colder air will filter in across the region Tuesday afternoon. Lake
enhance and lake effect snows will develop south and southeast of
both lakes.

Outlook...

Wednesday... Widespread ifr in periods of snow.

Thursday and Saturday... Areas of MVFR ifr with snow showers likely.

Marine
Deepening low pressure system will track eastward from the upper
midwest to the lower great lakes by Tuesday. Winds will rapidly
increase in the wake of this system cold front Tuesday through
Thursday prompting a prolonged period of small craft advisory
conditions areawide.

Buf watches warnings advisories
Ny... Winter storm warning from midnight tonight to 7 pm est
Wednesday for nyz003>008.

Winter weather advisory from 10 pm this evening to 1 pm est
Wednesday for nyz001-002-010-011-013-014-021.

Lake effect snow warning from 10 pm this evening to 7 pm est
Wednesday for nyz012-019-020-085.

Marine... Small craft advisory from 4 am Tuesday to 1 am est Thursday
for lez020-040-041.

Small craft advisory from 7 am Tuesday to 4 am est
Thursday for loz042-043.

Small craft advisory from 10 am Tuesday to 7 pm est
Thursday for loz044-045.

Synopsis... Ar
near term... Ar
short term... Hitchcock
long term... Wood
aviation... Ar
marine... Ar


Weather Reporting Stations
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Stations Dist Age Wind Air TempWater Temp WavesPressureDewPt
RPRN6 - Rochester, NY 7 mi37 min ESE 14 G 17 25°F 1015.6 hPa (-1.3)
RCRN6 - 9052058 - Rochester, NY 7 mi49 min 26°F 1015 hPa
OLCN6 - Olcott Harbor, NY 59 mi37 min ESE 8 G 11 23°F 1014.9 hPa (-1.7)

Wind History for Oswego, NY
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Airport Reports
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AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Rochester, Greater Rochester International Airport, NY4 mi43 minE 99.00 miLight Snow25°F21°F85%1015.2 hPa

Wind History from ROC (wind in knots)
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Last 24hrSW8W10W8SW6SW10SW13SW11SW9SW10SW9W5W5NW5N5N7NW4N5NE4CalmNE5E4E5E8E9
1 day agoCalmNW4W6W4W5W6W7SW9W7W9W10W9W8W7W8W13
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2 days agoSW7SW9SW6SW9SW12SW7SW7SW5SW7SW10SW7SW9SW7SW8SW7S5SW6SW7SW5S7SW8W3W4W3

Tide / Current Tables for
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Weather Map and Satellite Images
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Weather Map
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IR Satellite Image from GEOS
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GOES Local Image of Northeast    EDIT
Geos

Wind Forecast for Buffalo, NY (17,4,5,8)
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Ground Weather Radar Station Buffalo, NY
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Disclaimer:
The information on this web site has not been checked for accuracy. It is for entertainment purposes only and should be independently verified before using for any other reason. There are five sources. 1) Documents and manuals from a variety of sources. These have not been checked for accuracy and in many cases have not even been read by anyone associated with L-36.com. I have no idea of they are useful or accurate, I leave that to the reader. 2) Articles others have written and submitted. If you have questions on these, please contact the author. 3) Articles that represent my personal opinions. These are intended to promote thought and for entertainment. These are not intended to be fact, they are my opinions. 4) Small programs that generate result presented on a web page. Like any computer program, these may and in some cases do have errors. Almost all of these also make simplifying assumptions so they are not totally accurate even if there are no errors. Please verify all results. 5) Weather information is from numerious of sources and is presented automatically. It is not checked for accuracy either by anyone at L-36.com or by the source which is typically the US Government. See the NOAA web site for their disclaimer. Finally, tide and current data on this site is from 2007 and 2008 data bases, which may contain even older data. Changes in harbors due to building or dredging change tides and currents and for that reason many of the locations presented are no longer supported by newer data bases. For example, there is very little tidal current data in newer data bases so current data is likely wrong to some extent. This data is NOT FOR NAVIGATION. See the XTide disclaimer for details. In addition, tide and current are influenced by storms, river flow, and other factors beyond the ability of any predictive program.