From waterman@enfo.com Thu Mar 31 12:56:12 2005 Return-Path: Received: from denali.enfo.com ([199.45.135.12]) by bcn.boulder.co.us (8.12.10/8.12.10/ITS-6.0/test-bcn) with ESMTP id j2VJu4fj023343 for ; Thu, 31 Mar 2005 12:56:05 -0700 (MST) Received: (from waterman@localhost) by denali.enfo.com (8.9.0/8.9.0) id MAA02038 for waterman@bcn.boulder.co.us; Thu, 31 Mar 2005 12:54:12 -0700 (MST) Received: from culter.Colorado.EDU (root@culter.colorado.edu [128.138.77.16]) by denali.enfo.com (8.9.0/8.9.0) with ESMTP id MAA02002 for ; Thu, 31 Mar 2005 12:47:31 -0700 (MST) Received: from culter.Colorado.EDU (markl@localhost [127.0.0.1]) by culter.Colorado.EDU (8.12.10/8.12.10/UnixOps+Hesiod) with ESMTP id j2VJmPgV005096; Thu, 31 Mar 2005 12:48:26 -0700 (MST) Received: (from markl@localhost) by culter.Colorado.EDU (8.12.10/8.12.8/Submit) id j2VJmHVp005095; Thu, 31 Mar 2005 12:48:17 -0700 (MST) Date: Thu, 31 Mar 2005 12:48:17 -0700 (MST) Message-Id: <200503311948.j2VJmHVp005095@culter.Colorado.EDU> From: Mark.Losleben@Colorado.EDU To: James.H.Butler@noaa.gov, James.Syvitski@Colorado.EDU, James.W.Elkins@noaa.gov, John.A.Ogren@noaa.gov, Scott.Entrekin@noaa.gov, ShelleyJ@ci.boulder.co.us, Stephen.A.Montzka@noaa.gov, Tfoster1@hotmail.com, Thayne.M.Thompson@noaa.gov, bert@crrel.usace.army.mil, billgage@ix.netcom.com, bradu@cires.colorado.edu, connie.woodhouse@noaa.gov, cosper@indra.com, deander@usgs.gov, deborah_luchsinger@nrel.gov, denisec55@yahoo.com, dpinesy@yahoo.com, erin.bissell@Colorado.EDU, george.kiladas@noaa.gov, jdheiden@aol.com, jean@nednet.net, jhardy@crrel41.crrel.usace.army.mil, johnk@ntsg.umt.edu, klaus.wolter@noaa.gov, larrylcnm@juno.com, litaori@telhai.ac.il, martin.hoerling@noaa.gov, matt@nednet.net, mayer@geop.ubc.ca, mokeefe136@aol.com, nicholas.pepin@port.ac.uk, nolan@ccc.atmos.colostate.edu, nwtlter@lists.colorado.edu, pedrick@culter.Colorado.EDU, pmb@rmtrr.org, rlax@kryos.Colorado.EDU, sdossett1@yahoo.com, sdossett@uiuc.edu, timbard99@yahoo.com, timothy.kittel@Colorado.EDU, waterman@enfo.com Subject: Mar 31, 2005 snowpack report Sender: waterman@enfo.com X-Spam-Checker-Version: SpamAssassin 2.64 (2004-01-11) on ruff X-Spam-Status: No, hits=-2.2 required=5.0 tests=BAYE_00,NO_REAL_NAME, SORTED_RECIPS autolearn=no version=2.64 X-Spam-Level: Status: O Greetings! Tomorrow is April 1, the traditional 'state of the snowpack' date for the western US. As such, conditions right now carry extra importance, because these are the values water managers and planners tend to rely upon more than at any other time of the year. The general snowpack pattern begun at the start of this season has pretty much remained constant this season at all spatial scales; Niwot (C1), the Front Range, the state of Colorado, and the western US. Today, March 31, 2005, the hand measurement at C1 (special thanks to Kurt Chowanski for making this possible today!) shows 11.625" of water in the 40" snowpack at C1. This is 90% of the manual record average and close to the earlier season values (90%, 98%, 92% at the end of December, January, and February, respectively). In comparison, there was almost 5" less water in last years snowpack at this time. According to the Snotel NRCS database, Niwot has 12.4" SWE (89% of average), and the cumulative winter precipitation is 14.3" (99% of average) at C1. As in past months, this shows the Snowpack Index to be a bit less than one, meaning a little less than usual of the precipitation is stored in the form of snow for later spring and summer water availability. Our South Platte basin snowpack is 85% of average (83% for winter precipitation) which just barely puts it in last place of the states basins. The Laramie/N. Platte and Yampa/White basins are essentially the, with 86% and 87% of average, respectively. Given the steady pattern this year, it is unlikely that the S. Platte reaches average conditions by the time of historical peak in latter April, because it would need to receive 262% of average snowfall to do so. The highest snowpack honors again go to the southern basins, San Miguel/San Juan/ Dolores/Animas is147% of average (133% winter precipitation), and the Upper Rio Grande and Gunnison close have 142% and 137%, respectively. The Snowpack Index (SI) is greater than one in all of these basins. Colorado as a whole is 110% of average snowpack and an SI>1 (winter precipitation is 102%) Snowpack in the western US retain the season pattern as well. Washington and Oregon suffer with 31% and 37% of average (67% and 61% winter precipitation), and areas below 40 degrees north latitude continue to be above average, with some locations at historical highs (SW Utah). Arizona, New Mexico, the Great Basin sites in California, and Utah are at 161%, 142%, 139%, 137%, respectively, and all have SI's greater than, one (Utah SI=1). The downstream storage on the Colorado River should benefit somewhat from this seasons snowpack as the basin is at 120% of average (SI=1). The Columbia River basin, however is at 49% of average. So, this season may prove that there is more than El Nino or La Nina controlling the western US snowfall. The ENSO index has never been strongly off neutral, but this is a very strong El Nino winter precipitation signal. This may provide a valuable data point for the climate community to evaluate for controls on western US winter weather! Until next month, Mark Losleben 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 12.0 (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 7.0 10.125 16.75 17.0 (22nd) 12.375(13th) 19.75(30th) 95/96 7.50 12.00 17.5 20.375 18.75 6.125 (15th) 96/97 8.75 12.625 15.125 14.625 20.375 18.0 (15th) 97/98 7.0625 10.0 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 10.00 9.125 01/2002 2.625 4.25 6.19 7.563 0.0 02/2003 4.00 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 Average 5.409 7.819 10.242 12.908 13.266