MKWC archive forecast page For the time being, this page will (obviously) using the old MKWC web page design...Sorry for the inconvenience Please select a year and month and links of all available forecasts for that period will be given in the 'Select Forecast' menu. Select Year: 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 Select Month: Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Select Forecast: Sep 02 2003 (morning) Sep 02 2003 (afternoon) Sep 03 2003 (morning) Sep 03 2003 (afternoon) Sep 04 2003 (morning) Sep 04 2003 (afternoon) Sep 05 2003 (morning) Sep 05 2003 (afternoon) Sep 08 2003 (morning) Sep 08 2003 (afternoon) Sep 09 2003 (morning) Sep 09 2003 (afternoon) Sep 10 2003 (morning) Sep 10 2003 (afternoon) Sep 11 2003 (morning) Sep 11 2003 (afternoon) Sep 12 2003 (morning) Sep 12 2003 (afternoon) Sep 15 2003 (morning) Sep 15 2003 (afternoon) Sep 16 2003 (morning) Sep 16 2003 (afternoon) Sep 17 2003 (morning) Sep 17 2003 (afternoon) Sep 18 2003 (afternoon) Sep 19 2003 (morning) Sep 19 2003 (afternoon) Sep 22 2003 (morning) Sep 22 2003 (afternoon) Sep 23 2003 (morning) Sep 23 2003 (afternoon) Sep 24 2003 (morning) Sep 24 2003 (afternoon) Sep 25 2003 (morning) Sep 25 2003 (afternoon) Sep 26 2003 (morning) Sep 26 2003 (afternoon) Sep 29 2003 (morning) Sep 29 2003 (afternoon) Sep 30 2003 (morning) Sep 30 2003 (afternoon) Selection: 2003 09 Sep 03 2003 (afternoon)

Warnings None Cloud Cover and Precipitation Forecast Clear skies and dry air is expected at the summit through the night. Summary of Key Meteorological Variables Summit temperatures will be near 5 C tonight and 4.5 C tomorrow morning. Precipitable water is expected to be in the 2 to 2.5 mm range for the first half of the night and 1.75 to 2.25 mm during the second half. Winds will be from the northeast at 15 to 25 mph for today and 10 to 20 mph tonight. Shear will be between 25 to 35 mph through the night. Discussion The tradewind inversion will remain very strong and well-defined at 6 to 8 thousand feet through the forecast period. This will help limit low-level moisture ascent and keep the summit dry during this time. Daytime clouds will be very minimal and short-lived, if at all. No high clouds are expected to be within 700 km of the summit through Friday night. Winds are expected to drop from the 15 to 25 mph for tonight and settle in the 10 to 20 mph range for the remainder of the forecast period. Wind direction will start out from the northeast, but will be veering to easterlies as the next 2 to 3 days progress. Summit temperatures will be near 4.5 to 5 C for tonight and 3.5 to 4 C for Thursday and Friday night. Precipitable water is expected to decline from near 2 mm for tonight to about 1.6 mm for tomorrow night, and around 1.4 mm on Friday night. The mid/low level ridge will maintain control of summit weather over the next 3 to 5 days. The large-scale subsidence induced by this ridge will help keep the tradewind inversion quite strong and summit temperatures relatively warm during this time. The core of the ridge is expected to slide to the north-northwest of the Islands over the next 24 to 48 hours. This will help decrease precipitable water as the extra subsidence dries out the 500 to 300 mb layer. Meanwhile, clear skies are also expected through Friday night. This is mostly in response to the lack of winds/forcing aloft to bring/develop high clouds in the summit region. Part of this is due to the lack of convective activity and their associated cirrus exhaust to the south of the Islands (i.e. the tropics). As a result, there aren't any clouds to be blown over the summit by the winds aloft. Some believe that the lack of convection is the result of Jemina, which helped pull in most of the available moisture/energy in the tropics. Aside from the storm's wake where lots of residual vorticity persists, convective activity behind and to some extent in front of the storm would be limited. This appears to be the case here. Regardless, excellent conditions are expected through Friday, whatever unproven theories contributed to this weather. Astronomical Observing Quality Guidance Vertical Profiles from MM5 (vertical coordinate is pressure in mb): 5 pm HST Wed 03 Sep (0300 UTC Thu 04 Sep) Seeing Cn2 8 pm HST Wed 03 Sep (0600 UTC Thu 04 Sep) Seeing Cn2 11 pm HST Wed 03 Sep (0900 UTC Thu 04 Sep) Seeing Cn2 2 am HST Thu 04 Sep (1200 UTC Thu 04 Sep) Seeing Cn2 5 am HST Thu 04 Sep (1500 UTC Thu 04 Sep) Seeing Cn2 8 am HST Thu 04 Sep (1800 UTC Thu 04 Sep) Seeing Cn2 Tonight's (Wednesday Night) Collage Seeing Cn2 Thursday Night's Collage (available after 0800 HST on Thursday) Seeing Cn2 Friday Night's Collage (available after 0800 HST on Friday) Seeing Cn2

3-day Forecast Summary (Latest GFS Trend)	8 pm HST Wed 03 Sep	2 am HST Thu 04 Sep	2 pm HST Thu 04 Sep	8 pm HST Thu 04 Sep	2 am HST Fri 05 Sep	2 pm HST Fri 05 Sep	8 pm HST Fri 05 Sep	2 am HST Sat 06 Sep	2 pm HST Sat 06 Sep
	0600 UTC Thu 04 Sep	1200 UTC Thu 04 Sep	0000 UTC Fri 05 Sep	0600 UTC Fri 05 Sep	1200 UTC Fri 05 Sep	0000 UTC Sat 06 Sep	0600 UTC Sat 06 Sep	1200 UTC Sat 06 Sep	0000 UTC Sun 07 Sep
PW (mm, summit upward)	2 to	1.75 to 2.25	1.5 to 2	1.4 to 1.9	1.4 to 1.9	1.4 to 1.9	1.25 to 1.75	1.1 to 1.6	1.1 to 1.6
Summit Temp (oC)	5	4.5	9.5	4	3.5	10	4	3.5	9.5
Wind Dir/Speed (mph)     Summit     19,000 ft (500 hPa)     24,500 ft (400 hPa)     31,000 ft (300 hPa)     35,000 ft (250 hPa)     40,000 ft (200 hPa)     46,000 ft (150 hPa)     54,000 ft (100 hPa)	NE/15 to 25 N/14 NW/10 WNW/13 WNW/14 WNW/13 WNW/3 ENE/8	NE/10 to 20 N/10 NW/10 W/17 WNW/19 WNW/20 W/9 ENE/11	ENE/10 to 20 NE/5 NNE/1 SW/11 WSW/18 WSW/22 WSW/13 E/13	NE/10 to 20 NE/9 E/4 SSW/14 SW/22 SW/24 SW/12 E/12	ENE/10 to 20 ENE/7 SSE/5 SW/22 SW/25 SW/23 SSW/11 ESE/12	E/10 to 20 SE/5 S/14 SSW/23 SSW/25 SSW/25 SSW/18 ESE/14	ESE/10 to 20 SE/8 S/18 SSW/25 SW/26 SW/23 SSW/14 E/15	ESE/10 to 20 SSE/10 S/20 SW/22 SW/25 SW/20 SSW/15 ESE/16	E/10 to 20 ESE/5 S/14 SW/15 SW/19 SW/19 SW/17 E/6

Night (HST)	Sun Set	Twilight End	Twilight Beg	Sun Rise	Moon Rise	Moon Set	Illum (%)	RA	Dec
Wed.Sep.03/Thu.Sep.04	18:44	19:50	4:53	5:58	N/A	0:29	59	17 25.5	-26 10
Thu.Sep.04/Fri.Sep.05	18:43	19:49	4:53	5:58	N/A	1:28	70	18 27.8	-27 14
Fri.Sep.05/Sat.Sep.06	18:43	19:48	4:53	5:59	N/A	2:29	80	19 29.8	-26 37

Forecast issued by: Ryan Lyman
rlyman@hawaii.edu
(808) 932-2323

Next update at 10 am HST (2000 UTC) Thursday 04 September 2003.
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This page was last modified on: Wed, Apr 22 2009 - 2058 UTC
Send comments to: Ryan Lyman