Mammoth Mountain Ski Patrol 2019-20 Storm Summary - Sesame Snow Study Site 9,000' (2,743m)
Date	HN24(")	Base Depth	SWE	Rain	% Density	StormSnow "	Storm SWE "	Season Snow	Season SWE	Season Precip	Base Hi Temp	Base Lo Temp	Notes
11/20/2019	1.0	1.0	0.05	0.03
11/21/2019	1.0	1.5	0.10
11/22/2019	T	1.0	0.02			2.0	0.17	2.0	0.17	0.20
11/27/2019	18.0	18.0	1.75		10						26	7	Not the best base building snow.
11/28/2019	13.0	28.0	0.90		7						16	11	Blower pow…control the fever
11/29/2019	12.5	37.0	0.70		6						13	2	Immersion and hitting hidden obstacles are real!  Amazing powder skiing if you survive.
11/30/2019	8.0	35.0	0.50		6	51.5	3.85	53.5	4.02	4.05	14	4	Increased SW winds
Nov. Total	53.5		6.02	0.03
12/1/2019	7.0	36.0	0.65		9						28	8	Seeing good settlement continued SW winds
12/2/2019	12.0	42.0	1.35		11	19.0	2.00	70.5	6.02	6.05	29	26	Variable conditions but we have a great base!
12/5/2019	7.0	41.0	0.70		10	7.0	0.70	77.5	6.72	6.75	30	22	Snow fell during ops hrs on 12/4.  Period of strong SW winds overnight
12/7/2019	T	37.0	0.07								39	27	6" and 1.1"H2o fell during ops hrs will be included on 12/8
12/8/2019	19.0	53.0	2.70		14	19.0	2.77	96.5	9.49	9.52	31	25
12/12/2019	T	44.5		0.10				96.5	9.49	9.62	36	29	Started as snow around 5:45 then turned to rain
12/14/2019	5.0	46.0	1.10		22	5.0	1.10	101.5	10.59	10.72	36	23	3.5" /.66" fell after operating hours 12/13. Good skiing most places
12/15/2019	2.0	47.0	0.26		15	2.0	0.26	103.5	10.85	11.02	23	13	Puff the powder dragon
Date	HN24(")	Base Depth	SWE	Rain	% Density	StormSnow "	Storm SWE "	Season Snow	Season SWE	Season Precip	Base Hi Temp	Base Lo Temp	Notes
12/23/2019	10.0	50.0	1.10		11			113.5	11.95	12.12	33	21	Hero skiing but poor visibility.
12/24/2019	5.0	54.0	0.35		7	15.0	1.45	118.5	12.30	12.47	25	19	Very reactive upper mtn with lots of wind loading mid morning.  Hero skiing
12/25/2019	1.0	53.0	0.03		3						21	12	Poof
12/26/2019	2.5	54.0	0.30		12						19	12	Jasco winds with poor visibilty
12/27/2019	1.5	55.0	0.09		6	5.0	0.42	123.5	12.72	12.89	19	11	Fresno bowl/back 23 filling in
12/30/2019	1.0	49.5	0.04		4	1.0	0.04	124.5	12.74	12.93	33	21
Dec Total	73.0		8.74	0.10
1/10/2020	1.0	44.5	0.05		5	1.0	0.05	125.5	12.79	12.98	24	13
Date	HN24(")	Base Depth	SWE	Rain	% Density	StormSnow "	Storm SWE "	Season Snow	Season SWE	Season Precip	Base Hi Temp	Base Lo Temp	Notes
1/17/2020	9.0	49.0	0.90		10	9.0	0.90	134.5	13.69	13.88	26	10	Strong SW winds. Evidence of naturals upper mtn. Snow fell from 3pm to 9pm 1/16
1/21/2020	T	46.0	0.03								37	23
1/22/2020	T	47.0	0.07				0.10	134.5	13.79	13.98	28	23	Upper mtn received around an inch from the past two days.  Iso pockets from wind up to 6"
Jan Total	10.0		1.05
2/3/2020	T	44.5	0.02				0.02	134.5	13.81	14.00	12	2
Feb Total	T		0.02
3/1/2020	8.5	46.0	0.65		8			143.0			36	18	3"/.26"H20 of the total fell up to midnight on 2/29
3/2/2020	2.0	45.0	0.22		11	10.5	0.87	145.0	14.68	14.87	24	9	2" fell during ops on 3/1. Jasco wind started around noon and stripped upper mtn.
3/8/2020	2.0	39.0	0.20		10	2.0	0.20	147.0	14.88	15.07	26	12	All snow fell during ops hrs 3/7  followed by strong WSW turning to SW until 9pm
3/11/2020	1.5	40.0	0.10		10	1.5	0.10	148.0	14.98	15.17
													OPERATIONS SUSPENDED TO PUBLIC EFFECTIVE 3/15/20  COVID 19
3/14/2020	1.5	38.0	0.13		46						43	24	H2o is high due to melt on board before collecting. Density will reflect .7 measured
3/15/2020	6.5	45.0	0.80		12						24	20
3/16/2020	15.0	57.0	1.51		10						26	21	R1 D1 isolated activity on mid mtn.
3/17/2020	14.0	65.0	0.92		7	37.0	3.36	185.0	18.34	18.53	26	9	Evidence of naturals on upper mtn.
Date	HN24(")	Base Depth	SWE	Rain	% Density	StormSnow "	Storm SWE "	Season Snow	Season SWE	Season Precip	Base Hi Temp	Base Lo Temp	Notes
3/18/2020	0.5	63.0	0.30		10	0.5	0.30	185.5	18.37	18.56	23	8	Evidence of wind loading and slabbing overnight.
3/19/2020	7.0	66.5	0.42		6						24	10
3/20/2020	T	64.0	0.02			7.0	0.44	192.5	18.81	19.00
3/22/2020	1.5	60.0	0.16		11						26	16	Light ENE winds
3/23/2020	3.5	62.0	0.20		6						32	20	Light SW winds
3/24/2020	1.5	61.5	0.15		10	6.5	0.51	199.0	19.32	19.51	27	17
3/25/2020	4.0	65.0	0.40		10			203.0	19.72	19.91	23	12
3/26/2020	10.0	72.0	0.53		6	14.0	0.93	213.0	20.26	20.45	21	11
3/27/2020	1.5	66.0	0.11		7	1.5	0.11	214.5	20.37	20.56	26	5
3/29/2020	2.5	67.0	0.24		10						29	19
3/30/2020	1.0	67.0	0.11		10	3.5	0.35	218.0	20.72	20.91	28	19
March Total	84.0		7.17
Date	HN24(")	Base Depth	SWE	Rain	% Density	StormSnow "	Storm SWE "	Season Snow	Season SWE	Season Precip	Base Hi Temp	Base Lo Temp	Notes
4/5/2020	4.0	61.0	0.53		12.5	4.0	0.53	222.0	21.25	21.44	37	24
4/6/2020	35.0	90.0	3.30		9						24	17
4/7/2020	5.5	92.0	0.45		8	40.5	3.75	262.5	25.00	25.78	27	14	snow fell during morning hrs of 4/6. Increase Precip from Met one was most likely from winds and tree spit. .45"H2o from tube
4/8/2020	2.0	87.0	0.30		20						30	20
4/9/2020	4.0	87.0	0.47		12						33	23
4/10/2020	1.5	85.0	0.15		10	7.5	0.92	272.0	26.22	27.87	30	14	Another SWE/H2o discrepency  .15/.3.  .3 will be added to season precip while .15 to Season SWE
4/13/2020	T	76.0	0.02					272.0	26.22	27.87	45	24	Thunder Snow Pm of 4/12
4/17/2020	T			0.05							48	27	Afternoon light showers
4/18/2020	3.0	69.0	0.50		17	3.0	0.55	275.0	26.77	28.42	43	28	Thunder snow in afternoon and evening of 4/17.  Large graupel at base of boards
4/21/2020	2.0	65.0	0.27		12.5	2.0	0.27	277.0	27.04	28.69	39	25	Afternoonn cell on 4/20
April Total	53.0		5.49	0.05
Date	HN24(")	Base Depth	SWE	Rain	% Density	StormSnow "	Storm SWE "	Season Snow	Season SWE	Season Precip	Base Hi Temp	Base Lo Temp	Notes
5/18/2020		1.0		0.74						29.43	34	40	All rain with strong winds
5/19/2020	2.5	3.5	0.50	0.31	20	2.5	0.50	279.5	27.54	30.24	29	33
May Total	2.5		0.50	1.05
Season Totals								279.5	27.54	30.24			Discrepency between Met One at Sesame is due to SWE measurements in field
Units for Base Depth, New Snow, Storm Total, and Season Snowfall are in inches.
SWE≡Snow Water Equivalent, the amount of water produced from melting a known volume of snow.  Measured in inches of H2O.
Season Precip includes SWE and rain since October 1st.
Units for 24 Hour Base Hi Temp and Base Lo Temp are degrees Fahrenheit.
Line breaks indicate clearing between storms, despite occasional consecutive days.
All data subject to revision.