Mammoth Mountain Ski Patrol 2018-19 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
10/2/2018	0.0	0.0		0.02							57	43
10/3/2018	0.0	0.0		0.60							46	38	.47" fell during day 10/2 after morning obs
10/4/2018	0.0	0.0		0.74							46	34	.19" fell during day 10/3. Snow level top ch 1.  Lower on N facing slopes observed during morning obs
10/5/2018	0.0	0.0		0.03						1.86	46	31	.03" during day 10/4.  First frost of the season.
10/7/2018	T	T		0.15						2.01	37	27	Afternoon and overnight cells from 10/6
11/22/2018	12.0	12.0	1.40	0.00	12						34	23	Met one was high.  Good pow but no base
11/23/2018	3.0	15.0	0.50	0.00	16						28	23	Had some snain around main lodge halfway up ch 1
11/24/2018	4.0	17.0	0.85	0.00	21	19.0	2.75	19.0	2.75	4.76	31	28	Storm warming trend
11/28/2018	11.0	24.5	1.45	0.00	13			30.0		6.21	34	28	4" fell overnight.  Rest fell during ops hrs.  Strong SW winds dimissed  as precip began.
11/29/2018	16.0	38.0	1.97	0.00	12						31	27	8" fell overnight and 8" during day.
11/30/2018	7.5	41.0	0.69	0.00	9	34.5	4.11	53.5	6.86	10.32	29	22	Kind pow fell overnight but affected by wind
Nov. Total	53.5		6.86					53.5
12/1/2018	1.0	39.0	0.13	0.00	13						27	16
12/2/2018	6.5	42.0	0.48	0.00	13						19	10
12/3/2018	T	37.5	0.01	0.00							29	16
12/4/2018	1.5	38.0	0.08	0.00	5						24	11	short break in systems
12/5/2018	4.0	40.0	0.40	0.00	10						26	25
12/6/2018	2.0	42.0	0.14	0.00	7	15.0	1.24	68.5	8.10	11.56	22	13
12/17/2018	4.0	34.0	0.50	0.00	13						40	26	Started around 4am continued through midday
12/18/2018	2.0	36.0	0.30	0.00	15	6.0	0.80	74.5	8.90	12.36	40	29	All fell during ops hrs 12/17
Date	HN24(")	Base Depth	SWE	Rain	% Density	StormSnow "	Storm SWE "	Season Snow	Season SWE	Season Precip	Base Hi Temp	Base Lo Temp	Notes
12/21/2018	1.0	35.0	0.10	0.00	10	1.0	0.10	75.5	9.00	12.46	47	26	Angry inch w/ strong SW winds
12/25/2018	4.5	38.0	0.70	0.00	15	4.5	0.70	79.5	9.70	13.16	33	16	White xmas!  All fell overnight
12/28/2018	1.0	38.0	0.05	0.00	5	1.0	0.06	81.0	9.75	13.21	16	6	NE storm.  Town got more snow 3"
Dec. Total	27.5		2.90					81.0
1/6/2019	16.0	52.0	1.40	0.00	9						29	16	1" and .18 fell during ops hrs on 1/5
1/7/2019	19.0	65.0	2.50	0.00	13	35.0	3.90	115.5	13.65	17.11	26	16	Damaging winds overnight.  Pwr loss at Main lodge from 10-12am
1/9/2019	2.5	61.0	0.26	0.00	10						33	26	Snow started around 5am and snowed heavu for ost of the morning
1/10/2019	6.5	64.0	0.84	0.00	13	9.0	1.10	124.5	15.09	17.21	30	20	All but last inch fell during ops hrs on 1/9.  Back ramp Ch 3 closed at noon due to upper mtn wind loading.
1/15/2019	3.0	66.0	0.20	0.00	7	3.0	0.20	127.5	15.29	17.41	23	13
1//16/2019	12.5	73.0	1.63	0.00	13	12.5	1.63	140.0	16.92	19.04	25	19	definitive clearing mid morning until mid afternoon.  Cleared storm board
Date	HN24(")	Base Depth	SWE	Rain	% Density	StormSnow "	Storm SWE "	Season Snow	Season SWE	Season Precip	Base Hi Temp	Base Lo Temp	Notes
1/17/2019	18.0	86.5	3.00	Y	17						31	25	all overnight.  Not as much as forecasted.  Lightning ceased snow safety work @ 05:30
1/18/2019	9.0	91.0	1.60	0.00	18	27.0	4.63	167.0	21.52	23.64	31	22	mostly wind transport and light snow showers during ops hrs.
1/21/2019	8.0	90.0	1.03	0.00	13	8.0	1.03	175.5	22.55	24.64	31	13	Great skiing.  Not much avalanche activity
Jan. Total	94.5		12.46					175.5
2/2/2019	12.0	86.5	1.00	0.00	8						40	27
2/3/2019	32.5	117.0	3.40	0.00	10						29	18	Boom!  16 during day and 16 overnight
2/4/2019	7.5	119.5	0.90	0.00	12						24	18	Getting cold…blower pow alert
2/5/2019	26.0	138.5	2.80	0.00	11						19	9	5.5 fell during ops hours and the rest overnight
2/6/2019	10.0	138.0	0.90	0.00	9	88.0	9.00	263.0	31.55	33.64	9	-3	Still snowing…Skies cleared at sweep.
Date	HN24(")	Base Depth	SWE	Rain	% Density	StormSnow "	Storm SWE "	Season Snow	Season SWE	Season Precip	Base Hi Temp	Base Lo Temp	Notes
2/9/2019	16.0	141.0	0.92	0.00	6						19	10
2/10/2019	13.0	144.5	0.96	0.00	7						17	14
2/11/2019	8.0	146.0	0.92	0.00	11	37.0	2.80		34.35		16	0
2/13/2019	5.0	140.0	0.70		14						30	20
2/14/2019	12.0	145.0	3.50	Y	28						32	23	6" and 1.7" h2o fell during ops hrs 2/13  No lifts opened due to high winds and lightning most of the day
2/15/2019	13.5	150.5	2.50	Y	19						32	16
2/16/2019	17.0	159.0	1.19		7						19	9	10" and .84 h2o fell during ops hrs 2/15
2/17/2019	13.0	163.0	0.85		7						16	6	12" and .55"h2o fell during ops 2/16
2/18/2019	5.0	159.0	0.31		6	65.5			43.40		16	6	2" and .2 h2o fell during ops 2/17
2/22/2019	5.5	153.5	0.26		4						17	5	Coold smoke!!  More please.  Limited results from ski cuts
2/23/2019	2.0	151.0	0.04		3	7.5	0.30		43.70		14	-3	Brrrr.
2/27/2019	4.5	144.5	0.52		12						34	22	Big Time settlement.  Limited results from ski cuts except for Hemlock
2/28/2019	5.0	148.0	0.83		17	9.5	1.35	383.0	45.05		29	23	Great skiing, snow has "pop"  Limited to no results from ski cuts.
Feb Total	207.5		22.50					383.0
3/1/2019	2.0	148.0	0.34		17						28	24
3/2/2019	6.0	152.0	0.50		8						31	24
3/3/2019	12.5	161.0	1.80		14				47.69		29	27
Date	HN24(")	Base Depth	SWE	Rain	% Density	StormSnow "	Storm SWE "	Season Snow	Season SWE	Season Precip	Base Hi Temp	Base Lo Temp	Notes
3/6/2019	12.0	166.0	2.10		17						29	26
3/7/2019	6.0	171.0	1.20		20						28	20
3/8/2019	0.5	171.0	0.14		28						31	15
3/9/2019	T	171.0	0.05								20	11
3/10/2019	5.0	172.5	0.25		5				51.43		24	11
3/12/2019	1.0	165.0	0.12		12				51.55		34	7
3/20/2019	7.0	161.5	0.67		9						42	24	sensitive soft slabs running far.  Good skiing debris and places that snow stuck
3/21/2019	1.0	160.0	0.08		8				52.30		33	21	30-40mph SW winds led to sensitive cornices
3/23/2019	1.0	158.0	0.08		8						33	18	Light winds…the inch was not angry
3/24/2019	4.0	162.0	0.48		13				52.86		26	9	Light winds continue.
3/28/2019	9.0	165.0	1.26		14						30	23	Widespread activity and Cornices
3/29/2019	0.5	164.0	0.09		18				54.21		29	18
March Total	67.5		9.16					450.5
4/2/2019	1.5	156.0	0.22		15						50	29
4/3/2019	5.0	160.5	0.70		15				55.13		30	24	Most fell during ops hrs 4/02
4/6/2019	0.5	155.0	0.10		20				55.23		41	23
Date	HN24(")	Base Depth	SWE	Rain	% Density	StormSnow "	Storm SWE "	Season Snow	Season SWE	Season Precip	Base Hi Temp	Base Lo Temp	Notes
4/9/2019	0.5	148.5	0.38		70				55.61		47	30
4/12/2019	1.5	147.5	0.13		9				55.74		36	19
4/16/2019	3.5	150.0	0.65		19				56.39		32	25
April Total	12.5		2.18					462.5
5/10/2019	1.5	89.0	0.35		23		0.35	464.0	56.74		53	28	Started of as rain around 2pm.  Turned to snow around 4pm
5/16/2019	7.5	89.0	1.15		16						38	29
5/17/2019	5.0	91.0	0.68		14	12.5	1.83	476.5	58.57		29	22	Active morning on upper hill with overnight windloading.
5/19/2019	2.5	91.5	0.35		14						44	23
5/20/2019	3.0	94.0	0.35		12	5.5					28	13
5/21/2019	T	89.5	0.06				0.76	482.0	59.33		34	22
5/22/2019	2.0	92.5	0.35								28	21
5/23/2019	4.0	95.0	0.39								33	21
5/24/2019	2.5	95.0	0.35								37	28
5/25/2019	0.5	95.0	0.27				1.36	491.0	60.75		36	27
Date	HN24(")	Base Depth	SWE	Rain	% Density	StormSnow "	Storm SWE "	Season Snow	Season SWE	Season Precip	Base Hi Temp	Base Lo Temp	Notes
5/27/2019	2.5	93.5	0.35				0.35	493.50	61.10		27	18
May Total	31.0		4.65
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.