Niwot Ridge LTER Snow Report for Dec 2007
Niwot Ridge LTER Snow Report for December 31st, 2007

Greetings and Happy New Year!

This fall at Niwot Ridge has been relatively dry until December. Storms at the beginning and end of December have brought the snow water equivalent (SWE) to just below average. While Niwot and the South Platte River Basin are less snowy than last December, Colorado and much of the Western US is more snowy now than last December.

The ENSO Diagnostic Discussion issued by the NOAA Climate Prediction Center/NCEP predicts that the current La Nina conditions will continue into the spring of 2008, with expected above average precipitation in the Northern Rockies, and Pacific Northwest. Current snowpack conditions agree with the above expected La Nina impacts.

Hand measurements made at Niwot Ridge C-1 on December 31st, 2007 show 5.45 inches of snow water equivalent (SWE) for 98% of the average hand measurements, and a snow depth of 22.5 inches. SNOTEL is reporting 4.9 inches of SWE for 94% of average. The Niwot Ridge road and trails are all snow covered and the skiing is good.

The South Platte River Basin is at 95% of average SWE, and 96% of average precipitation. State wide the Arkansas River Basin has the highest percent of average SWE; the Laramie and North Platte River Basins have the lowest percent of average SWE (146%, 91% respectively). The Upper Rio Grande Basin has the highest percent of average precipitation, while the South Platte River Basin has the lowest percent of average precipitation (132%, 96%).

Across the West, Arizona, Colorado, New Mexico, Oregon, and Washington have above average SWE and above average cumulative precipitation. Washington has the highest percent of average SWE, while Arizona has the highest percent of cumulative precipitation (118%, 120%). The California Great Basin sites have both the lowest percent of average SWE and the lowest percent of cumulative precipitation (53%, 54%). The Snowpack Index (SI) is greater than one in Washington, and Oregon, and very close to one in the California Great Basin sites, Colorado, New Mexico, and Utah.

Until next month

Cheers

Kurt

Sno Tel Data  Niwot Ridge, C-1
Snow Water Content (inches)
Values are for the end of given month
except as noted for May and June

Season	Dec	Jan	Feb	Mar	Apr	May		Jun	
81/82	4.75	10.5	11.75	15.5	14.9	12	(17th)		
82/83	3.63		4.75	12.75	17	11.75	(30th)		
83/84	12.6	13.25	15	18.9	20.75				
84/85	3.75	6.25	8.5	10.25	8.75				
85/86	6.5	7.5	14	15.38	17.5				
86/87	6.25	8.75	11.25	12.75	11.75				
87/88	6.5	9.1	12.4	15.75	14.5				
88/89	5.5	7.6	11	10.25	5.6				
89/90	6.5	9.25	10.75	16.1	16.5				
90/91	3	5	7.1	9.38	10				
91/92	6.65	6.75	8.5	12.25	10.25				
92/93	5.75	6.75	10.75	14	15.875				
93/94	7.125	9.063	12.25	13.25	13.25	2.5	(18th)		
94/95	2.625	3.925	7	10.125	16.75	17	(22nd)	12.375(13th)	19.75(30th)
95/96	7.5	12	17.5	20.375	18.75	6.125	(15th)		
96/97	8.75	12.625	15.125	14.625	20.375	18	(15th)
97/98	7.0625	10	10.125	12.875	17.25	12.875	(15th)
98/99	3.25	6.625	8.375	9.125	14.125	14.25	(15th)
99/2000	3.5	7.5	10.625	12.375	7.625		
00/2001	4.375	5.375	7.125	10	9.125		
01/2002	2.625	4.25	6.19	7.563	0		
02/2003	4	5.25	8.5	16.75	14.375	11.44	(15th)
03/2004	2.75	4.813	7.75	7.875	10.125	3.69	(14th)
04/2005	4.875	7.7	9.5	11.625	12.875	12.25	(15th)
05/2006	5.625	8.375	9.5	13.25	6.75	0.875	(15th)
06/2007	9.25	11.5	14.375	15.25	16.75		
07/2008 5.45

Average	5.56	7.99	10.37	13.01	13.13