﻿334 
  0. 
  L. 
  Fassig 
  — 
  March 
  Weathe?' 
  in 
  the 
  United 
  States. 
  

  

  ing 
  relations 
  between 
  rainfall 
  and 
  mean 
  pressure 
  conditions 
  

   have 
  come 
  to 
  light 
  in 
  this 
  investigation. 
  The 
  decidedly 
  cold, 
  

   as 
  well 
  as 
  the 
  decidedly 
  warm 
  months, 
  were 
  deficient 
  in 
  rain- 
  

   fall. 
  In 
  each 
  case, 
  in 
  the 
  Middle 
  Atlantic 
  States, 
  ''high 
  area" 
  

   weather 
  prevailed, 
  the 
  region 
  being 
  either 
  well 
  within 
  the 
  

   Canadian 
  high 
  area 
  or 
  well 
  within 
  the 
  Atlantic 
  high 
  area. 
  

  

  The 
  extent 
  and 
  persistence 
  of 
  these 
  areas 
  of 
  high 
  pressure 
  

   over 
  any 
  region 
  define 
  the 
  geographic 
  limits 
  and 
  the 
  duration 
  

   of 
  a 
  drought. 
  Should 
  we 
  be 
  enabled, 
  by 
  further 
  study 
  of 
  the 
  

   problem, 
  to 
  learn 
  the 
  law 
  of 
  movement 
  of 
  these 
  high 
  areas, 
  it 
  

   will 
  become 
  a 
  comparatively 
  easy 
  problem 
  to 
  forecast 
  periods 
  

   of 
  drought 
  and 
  of 
  abundant 
  rains 
  in 
  the 
  United 
  States. 
  A 
  

   similar 
  method 
  is 
  already 
  practiced 
  in 
  India, 
  with 
  a 
  fair 
  measure 
  

   of 
  success, 
  in 
  forecasting 
  the 
  monsoon 
  and 
  the 
  winter 
  rains. 
  

  

  During 
  months 
  having 
  a 
  rainfall 
  above 
  the 
  normal 
  in 
  the 
  

   Middle 
  Atlantic 
  States, 
  this 
  region 
  was 
  almost 
  always 
  within 
  

   a 
  trough 
  of 
  average 
  low 
  pressure, 
  or 
  near 
  the 
  western 
  or 
  north- 
  

   ern 
  edge 
  of 
  the 
  Atlantic 
  high 
  area. 
  

  

  Average 
  j^ressure 
  distribution 
  and 
  the 
  paths 
  of 
  storms. 
  — 
  

   Some 
  interesting 
  and 
  suggestive 
  points 
  are 
  brought 
  out 
  by 
  

   charting 
  storm 
  tracks 
  in 
  connection 
  with 
  the 
  mean 
  pressure 
  

   distribution 
  during 
  the 
  month, 
  and 
  comparing 
  the 
  results 
  with 
  

   the 
  normal 
  distribution 
  of 
  pressure 
  and 
  storm 
  paths.* 
  

  

  Fig. 
  1 
  shows 
  the 
  normal 
  storm 
  tracks 
  during 
  March. 
  As 
  has 
  

   already 
  been 
  pointed 
  out, 
  during 
  March 
  the 
  continental 
  high 
  

   and 
  the 
  Atlantic 
  high 
  areas 
  are, 
  within 
  the 
  limits 
  of 
  the 
  United 
  

   States, 
  quite 
  equally 
  balanced 
  in 
  strength. 
  It 
  will 
  be 
  observed 
  

   that 
  the 
  storm 
  paths 
  while 
  normal 
  pressure 
  conditions 
  exist, 
  

   are 
  spread 
  quite 
  uniformly 
  over 
  the 
  country 
  from 
  the 
  Great 
  

   Lakes 
  to 
  the 
  Gulf, 
  and 
  converge 
  in 
  the 
  neighborhood 
  of 
  Labra- 
  

   dor 
  on 
  leaving 
  the 
  United 
  States. 
  I 
  have 
  plotted 
  the 
  storm 
  

   paths 
  of 
  March 
  in 
  connection 
  with 
  the 
  pressure 
  distribution 
  

   during 
  several 
  characteristic 
  abnormal 
  departures 
  of 
  pressure. 
  

   In 
  fig. 
  2 
  for 
  March, 
  1897, 
  they 
  are 
  found 
  in 
  a 
  narrow 
  band 
  

   extending 
  east 
  and 
  west 
  across 
  the 
  Lakes 
  and 
  down 
  the 
  St. 
  

   Lawrence 
  Yalley. 
  Fig. 
  3 
  for 
  March, 
  1882, 
  shows 
  a 
  crowding 
  

   together 
  of 
  the 
  storm 
  paths 
  into 
  a 
  comparatively 
  narrow 
  band, 
  

   extending 
  from 
  northeast 
  to 
  southwest, 
  across 
  the 
  Lake 
  Region 
  

   and 
  down 
  the 
  St. 
  Lawrence 
  Yalley. 
  In 
  fig. 
  4 
  for 
  March, 
  1885, 
  

   the 
  paths 
  are 
  mostly 
  north 
  of 
  their 
  usual 
  position, 
  with 
  some 
  

   along 
  the 
  Atlantic 
  coast, 
  while 
  the 
  central 
  portion 
  of 
  the 
  coun- 
  

   try 
  is 
  comparatively 
  free 
  from 
  storm 
  paths. 
  

  

  Mean 
  pressure 
  distribution 
  and 
  the 
  paths 
  of 
  West 
  Indian 
  

   hurricanes. 
  — 
  In 
  order 
  to 
  learn 
  whether 
  the 
  path 
  of 
  a 
  AYest 
  

   Indian 
  hurricane 
  is 
  to 
  any 
  extent 
  controlled 
  by 
  the 
  prevailing 
  

  

  * 
  F. 
  H. 
  Bigelow. 
  Storms, 
  storm 
  tracks 
  and 
  weather 
  forecasting. 
  United 
  States 
  

   Weather 
  Bureau, 
  Bull. 
  No. 
  20. 
  8°. 
  Washington, 
  1897. 
  87 
  pp. 
  

  

  